SIP Trust Provider DLL Replaced for Signing Bypass

Darshan Thummar@Mighty

•updated Jun 11, 2026•0•0•1

This rule detects network traffic on TCP port 445 (SMB) containing the string "wintrust.dll" in a case-insensitive manner. This specific DLL is associated with Windows Trust Provider functionality. The detection is flagged as 'trojan-activity' and is linked to MITRE ATT&CK technique T1553.003 (Code Signing: Code Signing Policy Modification) and tactic Defense Evasion, suggesting an attempt to bypass code signing policies by replacing or manipulating the wintrust.dll.