Vulnerability record · CVE-2009-2621 · published 28 July 2009

CVE-2009-2621: Squid-cache squid memory buffer overflow vulnerability

Squid Cache · Squid

Squid 3.0 through 3.0.STABLE16 and 3.1 through 3.1.0.11 does not properly enforce "buffer limits and related bound checks," which allows remote attackers to cause a denial of service via (1) an incomplete request or (2) a request with a large header size, related to (a) HttpMsg.cc and (b) client_side.cc.

5.0 CVSS 2.0 Medium EPSS 23% · top 2.3% CWE-119 · Memory buffer overflow

5.0CVSS 2.0 base score

23%EPSS exploitation probability, 30 days

NoNot in CISA KEV

1Affected product versions listed by NVD

16References

16 Jun 2026Last modified by NVD

Description

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

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

Squid Squid Cache

References

Link	Tags
http://secunia.com/advisories/36007
http://www.mandriva.com/security/advisories?name=MDVSA-2009:161
http://www.mandriva.com/security/advisories?name=MDVSA-2009:178
http://www.securityfocus.com/bid/35812
http://www.securitytracker.com/id?1022607
http://www.squid-cache.org/Advisories/SQUID-2009_2.txt	Vendor Advisory
http://www.squid-cache.org/Versions/v3/3.1/changesets/b9654.patch	Patch
http://www.vupen.com/english/advisories/2009/2013
http://secunia.com/advisories/36007
http://www.mandriva.com/security/advisories?name=MDVSA-2009:161
http://www.mandriva.com/security/advisories?name=MDVSA-2009:178
http://www.securityfocus.com/bid/35812
http://www.securitytracker.com/id?1022607
http://www.squid-cache.org/Advisories/SQUID-2009_2.txt	Vendor Advisory
http://www.squid-cache.org/Versions/v3/3.1/changesets/b9654.patch	Patch
http://www.vupen.com/english/advisories/2009/2013

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2009-2621), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.