CVE-2011-2766

Summary

CVECVE-2011-2766
StatePUBLISHED
Assignermitre
Source PriorityCVE Program / NVD first with legacy fallback
Published2011-09-23 10:55:03 UTC
Updated2026-04-29 01:13:23 UTC
DescriptionThe 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.

Risk And Classification

Primary CVSS: v2.0 7.5 from [email protected]

AV:N/AC:L/Au:N/C:P/I:P/A:P

Problem Types: CWE-287 | n/a

CVSS v2.0 Breakdown

Access Vector
Network
Access Complexity
Low
Authentication
None
Confidentiality
Partial
Integrity
Partial
Availability
Partial

AV:N/AC:L/Au:N/C:P/I:P/A:P

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Operating System Debian Debian Linux 5.0 All All All
Operating System Debian Debian Linux 6.0 All All All
Operating System Debian Debian Linux 7.0 All All All
Application Fast Cgi Project Fast Cgi All All All All

Vendor Declared Affected Products

SourceVendorProductVersionPlatforms
CNA Na N/a affected n/a Not specified

References

ReferenceSourceLinkTags
hermes.opensuse.org/messages/13154637 af854a3a-2127-422b-91ae-364da2661108 hermes.opensuse.org Broken Link
Support / Security / Advisories / / MDVSA-2012:001 | Mandriva af854a3a-2127-422b-91ae-364da2661108 www.mandriva.com Third Party Advisory
IBM X-Force Exchange af854a3a-2127-422b-91ae-364da2661108 exchange.xforce.ibmcloud.com Third Party Advisory, VDB Entry
Debian -- Security Information -- DSA-2327-1 libfcgi-perl af854a3a-2127-422b-91ae-364da2661108 www.debian.org Third Party Advisory
#607479 - libfcgi-perl: [CVE-2011-2766] After reloading some environment vars become constants, that will be used if not overruled by the headers of new requests. - Debian Bug report logs af854a3a-2127-422b-91ae-364da2661108 bugs.debian.org Exploit, Issue Tracking, Mailing List, Third Party Advisory
Bug #68380 for FCGI: FCGI-0.70 to 0.72 with perl5.12: CGI.pm receives CGI variables from previous requests af854a3a-2127-422b-91ae-364da2661108 rt.cpan.org Exploit, Patch, Third Party Advisory
Perl Fast CGI Module CGI Variables Authentication Security Bypass Vulnerability af854a3a-2127-422b-91ae-364da2661108 www.securityfocus.com Third Party Advisory, VDB Entry
Bug 736604 – CVE-2011-2766 perl-FCGI, fcgi: Certain environment variables shared between first and subsequent HTTP requests af854a3a-2127-422b-91ae-364da2661108 bugzilla.redhat.com Exploit, Issue Tracking, Third Party Advisory
oss-security - Re: CVE Request -- libfcgi-perl / perl-FCGI: Certain environment variables shared between first and subsequent HTTP requests af854a3a-2127-422b-91ae-364da2661108 www.openwall.com Mailing List, Third Party Advisory
hermes.opensuse.org/messages/13155253 af854a3a-2127-422b-91ae-364da2661108 hermes.opensuse.org Broken Link
oss-security - CVE Request -- libfcgi-perl / perl-FCGI: Certain environment variables shared between first and subsequent HTTP requests af854a3a-2127-422b-91ae-364da2661108 www.openwall.com Mailing List, Third Party Advisory
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Legacy QID Mappings

  • 900136 CBL-Mariner Linux Security Update for perl 5.30.3

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