Query: detection engineering for Bypass User Account Control
Matching passage: T1548.002 Bypass User Account Control. Tactics: privilege escalation. Description: Adversaries may bypass UAC mechanisms to elevate process privileges on system. Windows User Account Control (UAC) allows a program to elevate its privileges (tracked as integrity levels ranging from low to high) to perform a task under administrator-level permissions, possibly by prompting the user for confirmation. The impact to the user ranges from denying the operation under high enforcement to allowing the user to perform the action if they are in the local administrators group and click through the prompt or allowing them to enter an administrator password to complete the action.(Citation: TechNet How UAC Works) If the UAC protection level of a computer is set to anything but the highest level, certain Windows programs can elevate privileges or execute some elevated [Component Object Model](https://attack.mitre.org/techniques/T1559/001) objects without prompting the user through the UAC notification box.(Citation: TechNet Inside UAC)(Citation: MSDN COM Elevation) An example of this is use of [Rundll32](https://attack.mitre.org/techniques/T1218/011) to load a specifically crafted DLL which loads an auto-elevated [Component Object Model](https://attack.mitre.org/techniques/T1559/001) object and performs a file operation in a protected directory which would typically require elevated access. Malicious software may also be injected into a trusted process to gain elevated privileges without prompting a user.(Citation: Davidson Windows) Many methods have been discovered to bypass UAC. The Github readme page for UACME contains an extensive list of methods(Citation: Github UACMe) that have been discovered and implemented, but may not be a comprehensive list of bypasses. Additional bypass methods are regularly discovered and some used in the wild, such as: * <code>eventvwr.exe</code> can auto-elevate and execute a specified binary or script.(Citation: enigma0x3 Fileless UAC Bypass)(Citation: Fortinet Fareit) Another bypass is possible through some lateral movement techn
Near-miss passage: T1548.001 Setuid and Setgid. Tactics: privilege escalation. Description: An adversary may abuse configurations where an application has the setuid or setgid bits set in order to get code running in a different (and possibly more privileged) user’s context. On Linux or macOS, when the setuid or setgid bits are set for an application binary, the application will run with the privileges of the owning user or group respectively.(Citation: setuid man page) Normally an application is run in the current user’s context, regardless of which user or group owns the application. However, there are instances where programs need to be executed in an elevated context to function properly, but the user running them may not have the specific required privileges. Instead of creating an entry in the sudoers file, which must be done by root, any user can specify the setuid or setgid flag to be set for their own applications (i.e. [Linux and Mac Permissions](https://attack.mitre.org/techniques/T1222/002)). The <code>chmod</code> command can set these bits with bitmasking, <code>chmod 4777 [file]</code> or via shorthand naming, <code>chmod u+s [file]</code>. This will enable the setuid bit. To enable the setgid bit, <code>chmod 2775</code> and <code>chmod g+s</code> can be used. Adversaries can use this mechanism on their own malware to make sure they're able to execute in elevated contexts in the future.(Citation: OSX Keydnap malware) This abuse is often part of a "shell escape" or other actions to bypass an execution environment with restricted permissions. Alternatively, adversaries may choose to find and target vulnerable binaries with the setuid or setgid bits already enabled (i.e. [File and Directory Discovery](https://attack.mitre.org/techniques/T1083)). The setuid and setguid bits are indicated with an "s" instead of an "x" when viewing a file's attributes via <code>ls -l</code>. The <code>find</code> command can also be used to search for such files. For example, <code>find / -perm +4000 2>/dev/null</code> can be used to find files with setuid set an