Known exploited · Microsoft
CVE-2011-1889: Microsoft Forefront TMG Remote Code Execution Vulnerability
What it is
A remote code execution vulnerability exists in the Forefront Threat Management Gateway (TMG) Firewall Client Winsock provider that could allow code execution in the security context of the client application.
- Vendor
- Microsoft
- Product
- Forefront Threat Management Gateway (TMG)
- Added to KEV
- March 3, 2022
- CISA due date
- March 24, 2022
- Ransomware use
- Unknown
What CISA requires
Apply updates per vendor instructions.
Forensic triage
No
What to do now
- Find every instance of Forefront Threat Management Gateway (TMG) you run, including the forgotten ones, and check its version against the vendor advisory.
- Apply the vendor's fix or mitigation, before March 24, 2022 if you are bound by CISA's deadline, sooner if it faces the internet.
- Assume it was tried against you already: look for signs of exploitation from the date it was added, not from the day you patched.
References
H2 Security
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Start freeSource: CISA Known Exploited Vulnerabilities Catalog (public domain), catalog version 2026.10.01.