Query: stealth using Timestomp
Matching passage: T1070.006 Timestomp. Tactics: stealth. Description: Adversaries may modify file time attributes to hide new files or changes to existing files. Timestomping is a technique that modifies the timestamps of a file (the modify, access, create, and change times), often to mimic files that are in the same folder and blend malicious files with legitimate files. In Windows systems, both the `$STANDARD_INFORMATION` (`$SI`) and `$FILE_NAME` (`$FN`) attributes record times in a Master File Table (MFT) file.(Citation: Inversecos Timestomping 2022) `$SI` (dates/time stamps) is displayed to the end user, including in the File System view, while `$FN` is dealt with by the kernel.(Citation: Magnet Forensics) Modifying the `$SI` attribute is the most common method of timestomping because it can be modified at the user level using API calls. `$FN` timestomping, however, typically requires interacting with the system kernel or moving or renaming a file.(Citation: Inversecos Timestomping 2022) Adversaries modify timestamps on files so that they do not appear conspicuous to forensic investigators or file analysis tools. In order to evade detections that rely on identifying discrepancies between the `$SI` and `$FN` attributes, adversaries may also engage in “double timestomping” by modifying times on both attributes simultaneously.(Citation: Double Timestomping) In Linux systems and on ESXi servers, threat actors may attempt to perform timestomping using commands such as `touch -a -m -t <timestamp> <filename>` (which sets access and modification times to a specific value) or `touch -r <filename> <filename>` (which sets access and modification times to match those of another file).(Citation: Inversecos Linux Timestomping)(Citation: Juniper Networks ESXi Backdoor 2022) Timestomping may be used along with file name [Masquerading](https://attack.mitre.org/techniques/T1036) to hide malware and tools.(Citation: WindowsIR Anti-Forensic Techniques)
Near-miss passage: T1070.007 Clear Network Connection History and Configurations. Tactics: stealth. Description: Adversaries may clear or remove evidence of malicious network connections in order to clean up traces of their operations. Configuration settings as well as various artifacts that highlight connection history may be created on a system and/or in application logs from behaviors that require network connections, such as [Remote Services](https://attack.mitre.org/techniques/T1021) or [External Remote Services](https://attack.mitre.org/techniques/T1133). Defenders may use these artifacts to monitor or otherwise analyze network connections created by adversaries. Network connection history may be stored in various locations. For example, RDP connection history may be stored in Windows Registry values under (Citation: Microsoft RDP Removal): * <code>HKEY_CURRENT_USER\Software\Microsoft\Terminal Server Client\Default</code> * <code>HKEY_CURRENT_USER\Software\Microsoft\Terminal Server Client\Servers</code> Windows may also store information about recent RDP connections in files such as <code>C:\Users\\%username%\Documents\Default.rdp</code> and `C:\Users\%username%\AppData\Local\Microsoft\Terminal Server Client\Cache\`.(Citation: Moran RDPieces) Similarly, macOS and Linux hosts may store information highlighting connection history in system logs (such as those stored in `/Library/Logs` and/or `/var/log/`).(Citation: Apple Culprit Access)(Citation: FreeDesktop Journal)(Citation: Apple Unified Log Analysis Remote Login and Screen Sharing) Malicious network connections may also require changes to third-party applications or network configuration settings, such as [Disable or Modify System Firewall](https://attack.mitre.org/techniques/T1686) or tampering to enable [Proxy](https://attack.mitre.org/techniques/T1090). Adversaries may delete or modify this data to conceal indicators and/or impede defensive analysis.