Query: detection rule: Detects the load of RstrtMgr DLL (Restart Manager) by an uncommon process. This library has been used during ransomware
Matching passage: Sigma rule: Detects the load of RstrtMgr DLL (Restart Manager) by an uncommon process. This library has been used during ransomware. Logsource: windows / image_load. Rule: title: Load Of RstrtMgr.DLL By An Uncommon Process id: 3669afd2-9891-4534-a626-e5cf03810a61 related: - id: b48492dc-c5ef-4572-8dff-32bc241c15c8 type: derived status: test description: 'Detects the load of RstrtMgr DLL (Restart Manager) by an uncommon process. This library has been used during ransomware campaigns to kill processes that would prevent file encryption by locking them (e.g. Conti ransomware, Cactus ransomware). It has also recently been seen used by the BiBi wiper for Windows. It could also be used for anti-analysis purposes by shut downing specific processes. ' references: - https://www.crowdstrike.com/blog/windows-restart-manager-part-1/ - https://www.crowdstrike.com/blog/windows-restart-manager-part-2/ - https://web.archive.org/web/20231221193106/https://www.swascan.com/cactus-ransomware-malware-analysis/ - https://taiwan.postsen.com/business/88601/Hamas-hackers-use-data-destruction-software-BiBi-which-consumes-a-lot-of-processor-resources-to-wipe-Windows-computer-data--iThome.html author: Luc Génaux date: 2023-11-28 modified: 2026-07-28 tags: - attack.impact - attack.defense-impairment - attack.t1486 - attack.t1685 logsource: category: image_load product: windows detection: selection: - ImageLoaded|endswith: \RstrtMgr.dll - OriginalFileName: RstrtMgr.dll filter_main_generic: Image|startswith: - C:\$WINDOWS.~BT\ - C:\$WinREAgent\ - C:\Program Files (x86)\ - C:\Program Files\ - C:\ProgramData\ - C:\Windows\explorer.exe - C:\Windows\SoftwareDistribution\ - C:\Windows\SysNative\ - C:\Windows\System32\ - C:\Windows\SysWOW64\ - C:\Windows\WinSxS\ - C:\WUDownloadCache\ filter_main_user_software_installations: Image|startswith: C:\Users\ Image|contains|all: - \AppData\Local\Temp\is- - .tmp\ Image|endswith: .tmp filter_main_admin_software_installations: Image|startswith: C:\Windows\Temp\ filter_optional_onedrive_1: Image|startswith: C:\Users\ Image|endswith: - \AppData\Local\Microsoft\OneDrive\OneDrive.exe - \AppData\Local\Microsoft\OneDrive\OneDriveStandaloneUpdater.exe filter_optional_onedrive_2: Image|startswith: C:\Users\ Image|contains: \AppData\Local\Microsoft\OneDrive\ Image|endswith: \OneDrive.Sync.Service.exe condition: selection and not 1 of filter_main_* and not 1 of filter_optional_* falsepositives: - Other legitimate Windows processes not currently listed - Processes related to software installation level: low
Near-miss passage: Sigma rule: Detects potential abuse of WerFaultSecure.exe to dump Protected Process Light (PPL) processes like LSASS or to freeze se. Logsource: windows / process_creation. Rule: title: PPL Tampering Via WerFaultSecure id: 1f0b4cac-9c81-41f4-95d0-8475ff46b3e2 related: - id: 387df17d-3b04-448f-8669-9e7fd5e5fd8c type: similar - id: 8a2f4b1c-3d5e-4f7a-9b2c-1e4f6d8a9c2b type: similar status: experimental description: 'Detects potential abuse of WerFaultSecure.exe to dump Protected Process Light (PPL) processes like LSASS or to freeze security solutions (EDR/antivirus). This technique is used by tools such as EDR-Freeze and WSASS to bypass PPL protections and access sensitive information or disable security software. Distinct command line patterns help identify the specific tool: - WSASS usage typically shows: "WSASS.exe WerFaultSecure.exe [PID]" in ParentCommandLine - EDR-Freeze usage typically shows: "EDR-Freeze_[version].exe [PID] [timeout]" in ParentCommandLine Legitimate debugging operations using WerFaultSecure are rare in production environments and should be investigated. ' references: - https://www.zerosalarium.com/2025/09/EDR-Freeze-Puts-EDRs-Antivirus-Into-Coma.html - https://github.com/TwoSevenOneT/EDR-Freeze/blob/a7f61030b36fbde89871f393488f7075d2aa89f6/EDR-Freeze.cpp#L53 - https://www.zerosalarium.com/2025/09/Dumping-LSASS-With-WER-On-Modern-Windows-11.html - https://github.com/TwoSevenOneT/WSASS/blob/2c8fd9fa32143e7bc9f066e9511c6f8a57bc64b5/WSASS.cpp#L251 author: Jason (https://github.com/0xbcf) date: 2025-09-23 modified: 2025-11-23 tags: - attack.defense-impairment - attack.t1685 - attack.credential-access - attack.t1003.001 logsource: category: process_creation product: windows detection: selection_image: - Image|endswith: \WerFaultSecure.exe - OriginalFileName: WerFaultSecure.exe selection_args: CommandLine|contains|all: - ' /h ' - ' /pid ' - ' /tid ' - ' /encfile ' - ' /cancel ' - ' /type ' - ' 268310' condition: all of selection_* falsepositives: - Legitimate usage of WerFaultSecure for debugging purposes level: high regression_tests_path: regression_data/rules/windows/process_creation/proc_creation_win_werfaultsecure_abuse/info.yml