diff --git a/rules/privilege_escalation_uac_bypass_via_diskcleanup_scheduled_task_hijack.yml b/rules/privilege_escalation_uac_bypass_via_diskcleanup_scheduled_task_hijack.yml new file mode 100644 index 000000000..62cbef768 --- /dev/null +++ b/rules/privilege_escalation_uac_bypass_via_diskcleanup_scheduled_task_hijack.yml @@ -0,0 +1,42 @@ +name: UAC bypass via DiskCleanup scheduled task hijack +id: 683b0f04-15ab-4b89-8c4d-ee2077937c4e +version: 1.0.0 +description: | + Detects attempts to bypass User Account Control (UAC) by abusing the built-in + Windows Disk Cleanup scheduled task as a privilege escalation vector. + Adversaries commonly abuse trusted, auto-elevated Windows components to evade + UAC prompts and silently obtain high-integrity execution without requiring explicit + user consent. +labels: + tactic.id: TA0004 + tactic.name: Privilege Escalation + tactic.ref: https://attack.mitre.org/tactics/TA0004/ + technique.id: T1548 + technique.name: Abuse Elevation Control Mechanism + technique.ref: https://attack.mitre.org/techniques/T1548/ + subtechnique.id: T1548.002 + subtechnique.name: Bypass User Account Control + subtechnique.ref: https://attack.mitre.org/techniques/T1548/002/ +references: + - https://github.com/hfiref0x/UACME + - https://enigma0x3.net/2016/07/22/bypassing-uac-on-windows-10-using-disk-cleanup/ + +condition: > + spawn_process and + ps.token.integrity_level = 'HIGH' and + ps.cmdline imatches '*cleanmgr.exe*' and + thread.callstack.summary imatches 'ntdll.dll|KernelBase.dll|kernel32.dll|ubpm.dll|*' and + ps.exe not imatches + ( + '?:\\Windows\\System32\\cleanmgr.exe', + '?:\\Windows\\SysWOW64\\cleanmgr.exe', + '?:\\Windows\\System32\\taskhostw.exe', + '?:\\Windows\\System32\\taskhost.exe', + '?:\\Windows\\SysWOW64\\taskhost.exe' + ) +action: + - name: kill + +severity: high + +min-engine-version: 3.0.0