Sigma rule: Exploitation Activity of CVE-2025-59287 - WSUS Suspicious Child Process

Rule

Title

Exploitation Activity of CVE-2025-59287 - WSUS Suspicious Child Process

Status

experimental

Level

high

Author

Huntress Labs, Swachchhanda Shrawan Poudel (Nextron Systems)

Date

2025-10-31

File

rules-emerging-threats/2025/Exploits/CVE-2025-59287/proc_creation_win_exploit_cve_2025_59287.yml

Commit

ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects the creation of command-line interpreters (cmd.exe, powershell.exe) as child processes of Windows Server Update Services (WSUS) related process wsusservice.exe.
This behavior is a key indicator of exploitation for the critical remote code execution vulnerability such as CVE-2025-59287, where attackers spawn shells to conduct reconnaissance and further post-exploitation activities.

Log source

product

windows

category

process_creation

Detection

selection_parent_wsusservice:
    ParentImage|endswith: '\wsusservice.exe'
selection_parent_w3wp_wsuspool:
    ParentImage|endswith: '\w3wp.exe'
    ParentCommandLine|contains: 'WsusPool'
selection_child:
    Image|endswith:
        - '\cmd.exe'
        - '\powershell.exe'
        - '\pwsh.exe'
        - '\powershell_ise.exe'
condition: 1 of selection_parent_* and selection_child

False positives (as the rule lists them)

• If this activity is expected, consider filtering based on specific command lines, user context (e.g., `nt authority\network service`), or parent process command lines to reduce noise.

Tags

• attack.execution
• attack.initial-access
• attack.t1190
• attack.t1203
• cve.2025-59287
• detection.emerging-threats

CVEs this rule names

• CVE-2025-59287

MITRE ATT&CK ids this rule names

• T1190
• T1203

References

• https://unit42.paloaltonetworks.com/microsoft-cve-2025-59287/
• https://www.huntress.com/blog/exploitation-of-windows-server-update-services-remote-code-execution-vulnerability
• https://hawktrace.com/blog/CVE-2025-59287-UNAUTH

Read on 2026-11-03T00:58:21.399Z under licence sigma-drl-1.1@d5f4c36a from https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules-emerging-threats/2025/Exploits/CVE-2025-59287/proc_creation_win_exploit_cve_2025_59287.yml