CVE-2011-2883

Severity: critical (CVSS 9.3 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2011-07-21 · updated 2026-06-16
Weakness: CWE-20

Description

The NSEPA.NsepaCtrl.1 ActiveX control in nsepa.ocx in Citrix Access Gateway Enterprise Edition 8.1 before 8.1-67.7, 9.0 before 9.0-70.5, and 9.1 before 9.1-96.4 attempts to validate signed DLLs by checking the certificate subject, not the signature, which allows man-in-the-middle attackers to execute arbitrary code via HTTP header data referencing a DLL that was signed with a crafted certificate.

Affected products

Citrix Access Gateway: 8.1, 9.0, 9.1

References

http://labs.idefense.com/intelligence/vulnerabilities/display.php?id=928
http://labs.idefense.com/intelligence/vulnerabilities/display.php?id=928

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