CVE-2011-1889VulnerabilityPublished 03/03/2022Updated 10/24/2026

CVE-2011-1889: Microsoft Forefront TMG Remote Code Execution Vulnerability

Affects Microsoft Forefront Threat Management Gateway (TMG)Source CISA KEV

Severity

High

No CVSS score published yet

Exploitation: Actively exploited – in CISA KEV since 03/03/2022
KEV deadline: 03/24/2022
EPSS: 49.0% chance of exploitation in 30 days – higher than 98% of CVEs

What to do

CISA required action

Apply updates per vendor instructions.

nvd.nist.gov/vuln/detail/CVE-2011-1889 (opens in a new tab)

Description

CVE-2011-1889 is a remote code execution vulnerability in the Microsoft Forefront Threat Management Gateway (TMG) Firewall Client Winsock provider. This flaw allows an attacker to execute code in the security context of the client application. It has been exploited in the wild, indicating active use by threat actors. No specific affected versions or patch information is provided in the available data.

Summary

The vulnerability identified as CVE-2011-1889 affects the Forefront Threat Management Gateway (TMG) Firewall Client Winsock provider. It permits remote code execution, enabling an attacker to run arbitrary code with the privileges of the client application. The vulnerability is classified under CWE-119, indicating a memory safety issue such as a buffer overflow. The exploit has been observed in the wild, underscoring its practical risk. However, no explicit patch or remediation details are provided in the source data.

Impact

Successful exploitation of this vulnerability allows remote attackers to execute arbitrary code on the affected client system with the same privileges as the client application. This can lead to full compromise of the client environment depending on the application's privileges. The presence of known exploits in the wild increases the urgency and risk associated with this vulnerability.

Mitigation

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Due to the lack of explicit patch information, users should consult Microsoft’s official security advisories for Forefront TMG to determine if updates or mitigations are available. Until a fix is applied, minimizing exposure of the Forefront TMG client and applying principle of least privilege to client applications may reduce risk.

Weaknesses

CWE-119Buffer Errors (Memory Bounds) (opens in a new tab)

What to do

Description

AnalysisAI-generated, updated 10/24/2026, 10:25:25 UTC

Weaknesses

References

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