Patent Publication Number: US-11379583-B2

Title: Malware detection using a digital certificate

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This is a continuation application of U.S. patent application Ser. No. 14/752,874 filed Jun. 27, 2015, and entitled “MALWARE DETECTION USING A DIGITAL CERTIFICATE,” which is hereby incorporated by reference herein in its entirety. 
    
    
     TECHNICAL FIELD 
     This disclosure relates in general to the field of information security, and more particularly, to malware detection using a digital certificate. 
     BACKGROUND 
     The field of network security has become increasingly important in today&#39;s society. The Internet has enabled interconnection of different computer networks all over the world. In particular, the Internet provides a medium for exchanging data between different users connected to different computer networks via various types of client devices. While the use of the Internet has transformed business and personal communications, it has also been used as a vehicle for malicious operators to gain unauthorized access to computers and computer networks and for intentional or inadvertent disclosure of sensitive information. 
     Malicious software (“malware”) that infects a host computer may be able to perform any number of malicious actions, such as stealing sensitive information from a business or individual associated with the host computer, propagating to other host computers, and/or assisting with distributed denial of service attacks, sending out spam or malicious emails from the host computer, etc. Hence, significant administrative challenges remain for protecting computers and computer networks from malicious and inadvertent exploitation by malicious software and devices. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       To provide a more complete understanding of the present disclosure and features and advantages thereof, reference is made to the following description, taken in conjunction with the accompanying figures, wherein like reference numerals represent like parts, in which: 
         FIG. 1  is a simplified block diagram of a communication system for malware detection using a digital certificate in accordance with an embodiment of the present disclosure; 
         FIG. 2A  is a simplified block diagram of a communication system for malware detection using a digital certificate in accordance with an embodiment of the present disclosure; 
         FIG. 2B  is a simplified block diagram of a communication system for malware detection using a digital certificate in accordance with an embodiment of the present disclosure; 
         FIG. 3  is a simplified flowchart illustrating potential operations that may be associated with the communication system in accordance with an embodiment; 
         FIG. 4  is a block diagram illustrating an example computing system that is arranged in a point-to-point configuration in accordance with an embodiment; 
         FIG. 5  is a simplified block diagram associated with an example ARM ecosystem system on chip (SOC) of the present disclosure; and 
         FIG. 6  is a block diagram illustrating an example processor core in accordance with an embodiment. 
     
    
    
     The FIGURES of the drawings are not necessarily drawn to scale, as their dimensions can be varied considerably without departing from the scope of the present disclosure. 
     DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS 
     Example Embodiments 
       FIG. 1  is a simplified block diagram of a communication system  100  for malware detection using a digital certificate in accordance with an embodiment of the present disclosure. As illustrated in  FIG. 1 , an embodiment of communication system  100  can include an electronic device  102 , cloud services  104 , and a server  106 . Electronic device  102  can include memory  108 , a processor  110 , a digital certificate verification module  112 , and one or more files  114   a - 114   c . Each file  114   a - 114   c  can include a digital certificate  116   a - 116   c  respectively. Cloud services  104  and server  106  may each include a network digital certificate verification module  118 . Electronic device  102 , cloud services  104 , and server  106  may be in communication using network  126 . 
     Malicious device  120  may attempt to introduce or infect electronic device  102  with a malicious file  122 . Malicious file  122  can include an improper digital certificate  124  in an attempt to hide the true identity or purpose of malicious file  124 . Malicious device  120  may be in communication with electronic device  102  using network  126  or may be physically connected to electronic device  102  (e.g., through a Universal Serial Bus (USB) type connection). 
     Malicious file  122  may be malware or malicious software that infects a host computer (e.g., electronic device  102 ) to perform any number of malicious actions, such as stealing sensitive information from a business or individual associated with the host computer, propagating to other host computers, and/or assisting with distributed denial of service attacks, sending out spam or malicious emails from the host computer, etc. 
     Digital certificate validation module  112  can be configured to identify improper digital certificate  124  and can identify malicious file  122  as malware. For example, digital certificate validation module  112  can be configured to analyze each file  114   a - 114   c  and their digital certificate  116   a - 116   c  to determine if the digital certificate is improper. Combined with metadata about each file  114   a - 114   c  and each digital certificate  116   a - 116   c , an improper or malicious digital certificate can be identified. In a specific example, digital certification validation module  112  can analyze each digital certificate  116   a - 116   c  and determine if the code signing (e.g., Authenticode®) in each digital certificate  116   a - 115   c  matches the binary code. Code signing is the process of digitally signing executables and scripts to confirm the software author and attempt to guarantee that the code has not been altered or corrupted since it was signed by use of a cryptographic hash function. The cryptographic hash function can provide verification of the integrity of the digital certificate by indicating whether any changes have been made to the digital certificate. 
     Elements of  FIG. 1  may be coupled to one another through one or more interfaces employing any suitable connections (wired or wireless), which provide viable pathways for network (e.g., network  126 ) communications. Additionally, any one or more of these elements of  FIG. 1  may be combined or removed from the architecture based on particular configuration needs. Communication system  100  may include a configuration capable of transmission control protocol/Internet protocol (TCP/IP) communications for the transmission or reception of packets in a network. Communication systems  100   a  and  100   b  may also operate in conjunction with a user datagram protocol/IP (UDP/IP) or any other suitable protocol where appropriate and based on particular needs. 
     For purposes of illustrating certain example techniques of communication system  100 , it is important to understand the communications that may be traversing the network environment. The following foundational information may be viewed as a basis from which the present disclosure may be properly explained. 
     Current malware detection systems and methods often ignore or do not analyze files with digital certificates. This is because, a general trust is applied by certificate validation, informing systems that the file is trusted and the file can be executed. Some malware detection systems and security products use the knowledge of trust yielded by the digital certificate to bypass inspection of a file with the digital certificate. Therefore, one common way to bypass current malware detection systems and security products is to graft a digital certificate to a malicious file. For example, it is possible to modify a directory structure in a portable executable (PE) header and write a digital certificate to the malicious file in a way that the digital certificate or digital signing of the malicious file appears valid. What is needed is a system and method to analyze the validity of the digital certificate and determine if the digital certificate is improper. 
     A communication system for malware detection using a digital certificate, as outlined in  FIG. 1 , can resolve these issues (and others). Communication system  100  may be configured to analyze a digital certificate (e.g., digital certificate  116   a - 166   c ) for a file (e.g., file  114   a - 114   c ) and determine if the file has an improper digital certificate which could indicate that the file is malicious. For example, digital certification module  112  can analyze a file and determine if the file has a malformed certificate that is grafted on by modifying a PE header and directory. One way to determine this is to use Authenticode validation where the improper digital certificate will fail the Authenticode validation (e.g., bad hash). Also, an improper digital certificate can be identified if the certificate shares a fingerprint of a known digital certificate or the file hash is unique to the system. A digital signing using a certificate that contains the same fingerprint as a trusted certificate but has an invalid Authenticode is an indication of an improper digital certificate and is a strong indication of malware using a stolen certificate or one has been modified (e.g. through parasitic infection). In the parasitic infection case, minor errors can be eliminated by checking if the file is under windows file protection or other registrations of legitimate applications in the operating system. In an example, a fingerprint of a known certificate can be identified through a more intensive analysis using network digital certificate validation module  118 . For example a public key or thumbprint may be used to identify a known digital certificate. In another example, network digital certificate validation module  118  can be queried to determine if the fingerprint is the same as another digital certificate. Network digital certificate validation module  118  can also be used to determine the trust of a certificate by using network analysis techniques of large batch samples. 
     Turning to the infrastructure of  FIG. 1 , communication system  100  in accordance with an example embodiment is shown. Generally, communication system  100  can be implemented in any type or topology of networks. Network  126  represents a series of points or nodes of interconnected communication paths for receiving and transmitting packets of information that propagate through communication system  100 . Network  126  offers a communicative interface between nodes, and may be configured as any local area network (LAN), virtual local area network (VLAN), wide area network (WAN), wireless local area network (WLAN), metropolitan area network (MAN), Intranet, Extranet, virtual private network (VPN), and any other appropriate architecture or system that facilitates communications in a network environment, or any suitable combination thereof, including wired and/or wireless communication. 
     In communication system  100 , network traffic, which is inclusive of packets, frames, signals, data, etc., can be sent and received according to any suitable communication messaging protocols. Suitable communication messaging protocols can include a multi-layered scheme such as Open Systems Interconnection (OSI) model, or any derivations or variants thereof (e.g., Transmission Control Protocol/Internet Protocol (TCP/IP), user datagram protocol/IP (UDP/IP)). Additionally, radio signal communications over a cellular network may also be provided in communication system  100 . Suitable interfaces and infrastructure may be provided to enable communication with the cellular network. 
     The term “packet” as used herein, refers to a unit of data that can be routed between a source node and a destination node on a packet switched network. A packet includes a source network address and a destination network address. These network addresses can be Internet Protocol (IP) addresses in a TCP/IP messaging protocol. The term “data” as used herein, refers to any type of binary, numeric, voice, video, textual, or script data, or any type of source or object code, or any other suitable information in any appropriate format that may be communicated from one point to another in electronic devices and/or networks. Additionally, messages, requests, responses, and queries are forms of network traffic, and therefore, may comprise packets, frames, signals, data, etc. 
     In an example implementation, electronic devices  102 , cloud services  104 , and server  106  are network elements, which are meant to encompass network appliances, servers, routers, switches, gateways, bridges, load balancers, processors, modules, or any other suitable device, component, element, or object operable to exchange information in a network environment. Network elements may include any suitable hardware, software, components, modules, or objects that facilitate the operations thereof, as well as suitable interfaces for receiving, transmitting, and/or otherwise communicating data or information in a network environment. This may be inclusive of appropriate algorithms and communication protocols that allow for the effective exchange of data or information. 
     In regards to the internal structure associated with communication system  100 , electronic device  102 , cloud services  104 , and server  106  can include memory elements (e.g., memory  108 ) for storing information to be used in the operations outlined herein. Electronic device  102 , cloud services  104 , and server  106  may keep information in any suitable memory element (e.g., random access memory (RAM), read-only memory (ROM), erasable programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), application specific integrated circuit (ASIC), etc.), software, hardware, firmware, or in any other suitable component, device, element, or object where appropriate and based on particular needs. Any of the memory items discussed herein should be construed as being encompassed within the broad term ‘memory element.’ Moreover, the information being used, tracked, sent, or received in communication system  100  could be provided in any database, register, queue, table, cache, control list, or other storage structure, all of which can be referenced at any suitable timeframe. Any such storage options may also be included within the broad term ‘memory element’ as used herein. 
     In certain example implementations, the functions outlined herein may be implemented by logic encoded in one or more tangible media (e.g., embedded logic provided in an ASIC, digital signal processor (DSP) instructions, software (potentially inclusive of object code and source code) to be executed by a processor, or other similar machine, etc.), which may be inclusive of non-transitory computer-readable media. In some of these instances, memory elements can store data used for the operations described herein. This includes the memory elements being able to store software, logic, code, or processor instructions that are executed to carry out the activities described herein. 
     In an example implementation, network elements of communication system  100 , such as electronic device  102 , cloud services  104 , and server  106  may include software modules (e.g., digital certificate validation module  112  and network digital certificate validation module  118 ) to achieve, or to foster, operations as outlined herein. These modules may be suitably combined in any appropriate manner, which may be based on particular configuration and/or provisioning needs. In example embodiments, such operations may be carried out by hardware, implemented externally to these elements, or included in some other network device to achieve the intended functionality. Furthermore, the modules can be implemented as software, hardware, firmware, or any suitable combination thereof. These elements may also include software (or reciprocating software) that can coordinate with other network elements in order to achieve the operations, as outlined herein. 
     Additionally, electronic device  102 , cloud services  104 , and server  106  may include a processor (e.g., processor  110 ) that can execute software or an algorithm to perform activities as discussed herein. A processor can execute any type of instructions associated with the data to achieve the operations detailed herein. In one example, the processors could transform an element or an article (e.g., data) from one state or thing to another state or thing. In another example, the activities outlined herein may be implemented with fixed logic or programmable logic (e.g., software/computer instructions executed by a processor) and the elements identified herein could be some type of a programmable processor, programmable digital logic (e.g., a field programmable gate array (FPGA), an EPROM, an EEPROM) or an ASIC that includes digital logic, software, code, electronic instructions, or any suitable combination thereof. Any of the potential processing elements, modules, and machines described herein should be construed as being encompassed within the broad term ‘processor.’ 
     Electronic device  102  can be a network element and include, for example, desktop computers, laptop computers, mobile devices, personal digital assistants, smartphones, tablets, or other similar devices. Cloud services  104  is configured to provide cloud services to electronic device  102 . Cloud services may generally be defined as the use of computing resources that are delivered as a service over a network, such as the Internet. Typically, compute, storage, and network resources are offered in a cloud infrastructure, effectively shifting the workload from a local network to the cloud network. Server  106  can be a network element such as a server or virtual server and can be associated with clients, customers, endpoints, or end users wishing to initiate a communication in communication system  100  via some network (e.g., network  126 ). The term ‘server’ is inclusive of devices used to serve the requests of clients and/or perform some computational task on behalf of clients within communication system  100 . Although digital certificate validation module  112  is represented in  FIG. 1  as being located in electronic device  102 , this is for illustrative purposes only. Digital certificate validation module  112  could be combined or separated in any suitable configuration. Furthermore, digital certificate validation module  112  could be integrated with or distributed in another network accessible by electronic device  102  such as cloud services  104  or server  106 . 
     Turning to  FIG. 2A ,  FIG. 2A  is block diagram of an uncharacterized file  128 . Uncharacterized file  128  could be a trusted file, benign file, or a malicious file. Uncharacterized file  128  can include an image optional header  130 , section headers  134 , and sections  136 . Image optional header  130  can include a certificate table  132 . Image optional header  130  can provide information to a loader of uncharacterized file  128 . Certificate table  132  can indicate if the file includes one or more digital certificates. Section headers  134  can identify the content or data in sections  136 . Sections  136  includes data related to uncharacterized file  128  such as the payload of uncharacterized file  128 . Because uncharacterized file  128  does not include a digital certificate, it can be relatively easy for most malware detection systems and security products to identify uncharacterized file  128  as a malicious file if uncharacterized file  128  was malicious. 
     Turning to  FIG. 2B ,  FIG. 2B  is block diagram of a digitally signed file  138  with a digital certificate. If digitally signed file  138  was a malicious file, unlike uncharacterized file  128 , some malware detection systems and security products would not identify digitally signed file  138  as a malicious file. Digitally signed file  138  can include image optional header  130 , section, headers  134 , and sections  136 . Sections  136  can include certificate table  140 . Certificate table  140  can include content information  142 , certificates  144 , and signer information  146 . Certificates  144  can includes any digital certificates for digitally signed file  138 . For example, certificates  144  is illustrated as including certificate X509 certificate for publisher/timestamp  148 . Signer information  146  includes the signer information for each digital certificate in certificates  144 . For example, signer information  146  is illustrated as including digital certificate signer information  150  for certificate X509 certificate for publisher/timestamp  148 . Digital certificate signer information  150  can include counter signature  152 . 
     Digital certificate validation module  112  (or network digital certificate validation module  118 ) can be configured to analyze digitally signed file  138  and determine if digitally signed file  138  is malicious. For example, digital certificate validation module  112  can analyze certificate table  132  to determine if a security directory entry has been set in a way that would indicate a malicious file. In addition, digital certificate validation module  112  can analyze section headers  134  and determine if section sizes have been modified. If they were modified, then digitally signed file  138  may be malicious. Also, digital certification validation module  112  can analyzed content information  142  and determine if the Authenticode has been modified to match Authenticode for a known malware file. Digital certificate validation module  112  can also be configured to analyze certificate table  140  and determine if a certificate has been added from another legitimate file. Further, digital certificate validation module  112  can analyze certificate X509 certificate for publisher/timestamp  148  to determine if certificate details have been modified, which would indicate malicious activity. In addition, digital certification validation module  112  can analyze counter signature  152  in digital certificate signer information  150  to determine if counter signature  152  includes any unauthenticated attributes, which can indicate malicious activity. 
     Turning to  FIG. 3 ,  FIG. 3  is an example flowchart illustrating possible operations of a flow  300  that may be associated with malware detection using a digital certificate, in accordance with an embodiment. In an embodiment, one or more operations of flow  300  may be performed by digital certificate validation module  112  and network digital certificate validation module  118 . At  302 , a digital certificate associated with a file an analyzed. At  304 , the system determines if the digital certificate is proper. To determine if the digital certificate is proper, the system can analyze the file and data in the file that is related to the digital certificate. For example, the system can determine if code signing for the digital certificate matches binary code for the digital certificate, if the digital certificate has been grafted to the data by modifying a portable executable file header, if the digital certificate is the same or has the same finger print as another trusted digital certificate associated with different data, etc. If the digital certificate is not proper (e.g., if code signing for the digital certificate does not match binary code for the digital certificate, if the digital certificate has been grafted to the data by modifying a portable executable file header, if the digital certificate is the same or has the same finger print as another trusted digital certificate associated with different data, etc.), then the file may be classified as untrusted, as in  306 . If the digital certificate is proper, then the system determines if the digital certificate is trusted, as in  310 . For example, the data related to the digital certificate may be proper but the digital certificate itself may be untrusted (e.g., a digital certificate known to be associated with malware, etc.). If the digital certificate is not trusted, then file may be classified as untrusted as in  306 . If the digital certificate is trusted, then the file may be classified as trusted, as in  308 . 
     Turning to  FIG. 4 ,  FIG. 4  illustrates a computing system  400  that is arranged in a point-to-point (PtP) configuration according to an embodiment. In particular,  FIG. 4  shows a system where processors, memory, and input/output devices are interconnected by a number of point-to-point interfaces. Generally, one or more of the network elements of communication system  100  may be configured in the same or similar manner as computing system  400 . 
     As illustrated in  FIG. 4 , system  400  may include several processors, of which only two, processors  470  and  480 , are shown for clarity. While two processors  470  and  480  are shown, it is to be understood that an embodiment of system  400  may also include only one such processor. Processors  470  and  480  may each include a set of cores (i.e., processor cores  474 A and  474 B and processor cores  484 A and  484 B) to execute multiple threads of a program. The cores may be configured to execute instruction code in a manner similar to that discussed above with reference to  FIGS. 1-3 . Each processor  470 ,  480  may include at least one shared cache  471 ,  481 . Shared caches  471 ,  481  may store data (e.g., instructions) that are utilized by one or more components of processors  470 ,  480 , such as processor cores  474  and  484 . 
     Processors  470  and  480  may also each include integrated memory controller logic (MC)  472  and  482  to communicate with memory elements  432  and  434 . Memory elements  432  and/or  434  may store various data used by processors  470  and  480 . In alternative embodiments, memory controller logic  472  and  482  may be discrete logic separate from processors  470  and  480 . 
     Processors  470  and  480  may be any type of processor and may exchange data via a point-to-point (PtP) interface  450  using point-to-point interface circuits  478  and  488 , respectively. Processors  470  and  480  may each exchange data with a chipset  490  via individual point-to-point interfaces  452  and  454  using point-to-point interface circuits  476 ,  486 ,  494 , and  498 . Chipset  490  may also exchange data with a high-performance graphics circuit  438  via a high-performance graphics interface  439 , using an interface circuit  492 , which could be a PtP interface circuit. In alternative embodiments, any or all of the PtP links illustrated in  FIG. 4  could be implemented as a multi-drop bus rather than a PtP link. 
     Chipset  490  may be in communication with a bus  420  via an interface circuit  496 . Bus  420  may have one or more devices that communicate over it, such as a bus bridge  418  and I/O devices  416 . Via a bus  410 , bus bridge  418  may be in communication with other devices such as a keyboard/mouse  412  (or other input devices such as a touch screen, trackball, etc.), communication devices  426  (such as modems, network interface devices, or other types of communication devices that may communicate through a computer network  460 ), audio I/O devices  414 , and/or a data storage device  428 . Data storage device  428  may store code  430 , which may be executed by processors  470  and/or  480 . In alternative embodiments, any portions of the bus architectures could be implemented with one or more PtP links. 
     The computer system depicted in  FIG. 4  is a schematic illustration of an embodiment of a computing system that may be utilized to implement various embodiments discussed herein. It will be appreciated that various components of the system depicted in  FIG. 4  may be combined in a system-on-a-chip (SoC) architecture or in any other suitable configuration. For example, embodiments disclosed herein can be incorporated into systems including mobile devices such as smart cellular telephones, tablet computers, personal digital assistants, portable gaming devices, etc. It will be appreciated that these mobile devices may be provided with SoC architectures in at least some embodiments. 
     Turning to  FIG. 5 ,  FIG. 5  is a simplified block diagram associated with an example ARM ecosystem SOC  500  of the present disclosure. At least one example implementation of the present disclosure can include the determining the malware detection using a digital certificate features discussed herein and an ARM component. For example, the example of  FIG. 5  can be associated with any ARM core (e.g., A-9, A-15, etc.). Further, the architecture can be part of any type of tablet, smartphone (inclusive of Android™ phones, iPhones™), iPad™, Google Nexus™, Microsoft Surface™, personal computer, server, video processing components, laptop computer (inclusive of any type of notebook), Ultrabook™ system, any type of touch-enabled input device, etc. 
     In this example of  FIG. 5 , ARM ecosystem SOC  500  may include multiple cores  506 - 507 , an L2 cache control  508 , a bus interface unit  509 , an L2 cache  510 , a graphics processing unit (GPU)  515 , an interconnect  502 , a video codec  520 , and a liquid crystal display (LCD) I/F  525 , which may be associated with mobile industry processor interface (MIPI)/high-definition multimedia interface (HDMI) links that couple to an LCD. 
     ARM ecosystem SOC  500  may also include a subscriber identity module (SIM) I/F  530 , a boot read-only memory (ROM)  535 , a synchronous dynamic random access memory (SDRAM) controller  540 , a flash controller  545 , a serial peripheral interface (SPI) master  550 , a suitable power control  555 , a dynamic RAM (DRAM)  560 , and flash  565 . In addition, one or more example embodiments include one or more communication capabilities, interfaces, and features such as instances of Bluetooth™  570 , a 3G modem  575 , a global positioning system (GPS)  580 , and an 802.11 Wi-Fi  585 . 
     In operation, the example of  FIG. 5  can offer processing capabilities, along with relatively low power consumption to enable computing of various types (e.g., mobile computing, high-end digital home, servers, wireless infrastructure, etc.). In addition, such an architecture can enable any number of software applications (e.g., Android™, Adobe® Flash® Player, Java Platform Standard Edition (Java SE), JavaFX, Linux, Microsoft Windows Embedded, Symbian and Ubuntu, etc.). In at least one example embodiment, the core processor may implement an out-of-order superscalar pipeline with a coupled low-latency level-2 cache. 
     Turning to  FIG. 6 ,  FIG. 6  illustrates a processor core  600  according to an embodiment. Processor core  600  may be the core for any type of processor, such as a micro-processor, an embedded processor, a digital signal processor (DSP), a network processor, or other device to execute code. Although only one processor core  600  is illustrated in  FIG. 6 , a processor may alternatively include more than one of the processor core  600  illustrated in  FIG. 6 . For example, processor core  600  represents one example embodiment of processors cores  474   a ,  474   b ,  474   a , and  474   b  shown and described with reference to processors  470  and  480  of  FIG. 4 . Processor core  600  may be a single-threaded core or, for at least one embodiment, processor core  600  may be multithreaded in that it may include more than one hardware thread context (or “logical processor”) per core. 
       FIG. 6  also illustrates a memory  602  coupled to processor core  600  in accordance with an embodiment. Memory  602  may be any of a wide variety of memories (including various layers of memory hierarchy) as are known or otherwise available to those of skill in the art. Memory  602  may include code  604 , which may be one or more instructions, to be executed by processor core  600 . Processor core  600  can follow a program sequence of instructions indicated by code  604 . Each instruction enters a front-end logic  606  and is processed by one or more decoders  608 . The decoder may generate, as its output, a micro operation such as a fixed width micro operation in a predefined format, or may generate other instructions, microinstructions, or control signals that reflect the original code instruction. Front-end logic  606  also includes register renaming logic  610  and scheduling logic  612 , which generally allocate resources and queue the operation corresponding to the instruction for execution. 
     Processor core  600  can also include execution logic  614  having a set of execution units  616 - 1  through  616 -N. Some embodiments may include a number of execution units dedicated to specific functions or sets of functions. Other embodiments may include only one execution unit or one execution unit that can perform a particular function. Execution logic  614  performs the operations specified by code instructions. 
     After completion of execution of the operations specified by the code instructions, back-end logic  618  can retire the instructions of code  604 . In one embodiment, processor core  600  allows out of order execution but requires in order retirement of instructions. Retirement logic  620  may take a variety of known forms (e.g., re-order buffers or the like). In this manner, processor core  600  is transformed during execution of code  604 , at least in terms of the output generated by the decoder, hardware registers and tables utilized by register renaming logic  610 , and any registers (not shown) modified by execution logic  614 . 
     Although not illustrated in  FIG. 6 , a processor may include other elements on a chip with processor core  600 , at least some of which were shown and described herein with reference to  FIG. 4 . For example, as shown in  FIG. 4 , a processor may include memory control logic along with processor core  600 . The processor may include I/O control logic and/or may include I/O control logic integrated with memory control logic. 
     Note that with the examples provided herein, interaction may be described in terms of two, three, or more network elements. However, this has been done for purposes of clarity and example only. In certain cases, it may be easier to describe one or more of the functionalities of a given set of flows by only referencing a limited number of network elements. It should be appreciated that communication systems  100   a  and  100   b  and their teachings are readily scalable and can accommodate a large number of components, as well as more complicated/sophisticated arrangements and configurations. Accordingly, the examples provided should not limit the scope or inhibit the broad teachings of communication systems  100   a  and  100   b  as potentially applied to a myriad of other architectures. 
     It is also important to note that the operations in the preceding flow diagram (i.e.,  FIG. 3 ) illustrate only some of the possible correlating scenarios and patterns that may be executed by, or within, communication system  100 . Some of these operations may be deleted or removed where appropriate, or these operations may be modified or changed considerably without departing from the scope of the present disclosure. In addition, a number of these operations have been described as being executed concurrently with, or in parallel to, one or more additional operations. However, the timing of these operations may be altered considerably. The preceding operational flows have been offered for purposes of example and discussion. Substantial flexibility is provided by communication system  100  in that any suitable arrangements, chronologies, configurations, and timing mechanisms may be provided without departing from the teachings of the present disclosure. 
     Although the present disclosure has been described in detail with reference to particular arrangements and configurations, these example configurations and arrangements may be changed significantly without departing from the scope of the present disclosure. Moreover, certain components may be combined, separated, eliminated, or added based on particular needs and implementations. Additionally, although communication system  100  have been illustrated with reference to particular elements and operations that facilitate the communication process, these elements and operations may be replaced by any suitable architecture, protocols, and/or processes that achieve the intended functionality of communication system  100 . 
     Numerous other changes, substitutions, variations, alterations, and modifications may be ascertained to one skilled in the art and it is intended that the present disclosure encompass all such changes, substitutions, variations, alterations, and modifications as falling within the scope of the appended claims. In order to assist the United States Patent and Trademark Office (USPTO) and, additionally, any readers of any patent issued on this application in interpreting the claims appended hereto, Applicant wishes to note that the Applicant: (a) does not intend any of the appended claims to invoke paragraph six (6) of 35 U.S.C. section 112 as it exists on the date of the filing hereof unless the words “means for” or “step for” are specifically used in the particular claims; and (b) does not intend, by any statement in the specification, to limit this disclosure in any way that is not otherwise reflected in the appended claims. 
     OTHER NOTES AND EXAMPLES 
     Example C1 is at least one machine readable medium having one or more instructions that when executed by at least one processor, cause the at least one processor to analyze data related to a digital certificate, and assign a reputation to the digital certificate, wherein the reputation includes an indication if the data related to the digital certificate is proper. 
     In Example C2, the subject matter of Example C1 can optionally include where the analysis of the data related to the digital certificate includes determining if code signing for the digital certificate matches binary code for the digital certificate. 
     In Example C3, the subject matter of any one of Examples C1-C2 can optionally include where the code signing is Authenticode. 
     In Example C4, the subject matter of any one of Examples C1-C3 can optionally include where the analysis of the data related to the digital certificate includes determining if the digital certificate has been grafted to the data by modifying a portable executable file header. 
     In Example C5, the subject matter of any one of Examples C1-C4 can optionally include where the analysis of the data related to the digital certificate includes determining the digital certificate is the same as another trusted digital certificate associated with different data. 
     In Example C6, the subject matter of any one of Example C1-05 can optionally include where the digital certificate is classified as untrusted if the analysis of the data related to the digital certificate indicates that the data is improper. 
     In Example A1, an apparatus can include a digital certificate validation module configured to identify a file that includes a digital certificate and data related to the digital certificate, analyze the data related to the digital certificate, and assign a reputation to the file, where the reputation includes an indication if the data related to the digital certificate is proper. 
     In Example, A2, the subject matter of Example A1 can optionally include where the analysis of the data related to the digital certificate includes determining if code signing for the digital certificate matches binary code for the digital certificate. 
     In Example A3, the subject matter of any one of Examples A1-A2 can optionally include where the code signing is Authenticode. 
     In Example A4, the subject matter of any one of Examples A1-A3 can optionally include where the analysis of the data includes determining if the has been grafted to the data by modifying a portable executable file header. 
     In Example A5, the subject matter of any one of Examples A1-A4 can optionally include where the analysis of the data related to the digital certificate includes determining the digital certificate is the same as another trusted digital certificate associated with different data. 
     In Example A6, the subject matter of any one of Examples A1-A5 can optionally include where the file is classified as untrusted if the analysis of the data related to the digital certificate indicates that the data is improper. 
     Example M1 is a method including analyzing data related to a digital certificate, and assigning a reputation to the digital certificate, wherein the reputation includes an indication if the data related to the digital certificate is proper. 
     In Example M2, the subject matter of Example M1 can optionally include where the analysis of the data includes determining if code signing for the digital certificate matches binary code for the digital certificate. 
     In Example M3, the subject matter of any one of the Examples M1-M2 can optionally include where the code signing is Authenticode. 
     In Example M4, the subject matter of any one of the Examples M1-M3 can optionally include where the analysis of the data includes determining if the digital certificate has been grafted to the data by modifying a portable executable file header. 
     In Example M5, the subject matter of any one of the Examples M1-M4 can optionally include where the analysis of the data includes determining the digital certificate is the same as another trusted digital certificate associated with different data. 
     Example S1 is a system for malware detection using a digital certificate, the system including a digital certificate validation module configured for identifying data related to a digital certificate, analyzing the data related to the digital certificate, and assigning a reputation to the digital certificate, wherein the reputation includes an indication if the data is proper. 
     In Example S2, the subject matter of Example S1 can optionally include where the analysis of the data includes determining if code signing for the digital certificate matches binary code for the digital certificate. 
     In Example S3, the subject matter of any one of Examples S1 and S2 can optionally include where the analysis of the data includes determining if the digital certificate has been grafted to the data by modifying a portable executable file header. 
     Example X1 is a machine-readable storage medium including machine-readable instructions to implement a method or realize an apparatus as in any one of the Examples A1-A8, or M1-M7. Example Y1 is an apparatus comprising means for performing of any of the Example methods M1-M7. In Example Y2, the subject matter of Example Y1 can optionally include the means for performing the method comprising a processor and a memory. In Example Y3, the subject matter of Example Y2 can optionally include the memory comprising machine-readable instructions.