CVE-2011-2766

CVE-2011-2766 is a high-severity vulnerability in Fast Cgi Project Fast Cgi with a CVSS 2.0 base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-287.

Key facts

Description

The FCGI (aka Fast CGI) module 0.70 through 0.73 for Perl, as used by CGI::Fast, uses environment variable values from one request during processing of a later request, which allows remote attackers to bypass authentication via crafted HTTP headers.

Frequently asked questions

What is CVE-2011-2766?
The FCGI (aka Fast CGI) module 0.70 through 0.73 for Perl, as used by CGI::Fast, uses environment variable values from one request during processing of a later request, which allows remote attackers to bypass authentication via crafted HTTP headers.
How severe is CVE-2011-2766?
CVE-2011-2766 has a CVSS 2.0 base score of 7.5, rated high severity.
Is CVE-2011-2766 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 7% (94th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2011-2766?
CVE-2011-2766 primarily affects Fast Cgi Project Fast Cgi. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2011-2766?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2011-2766 published?
CVE-2011-2766 was published on 2011-09-23 and last updated on 2026-06-16.

References

Affected products (4)

Other CWE-287 (Improper Authentication) vulnerabilities

Browse all CWE-287 (Improper Authentication) vulnerabilities →