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Vulnerability record · CVE-2009-2855 · published 18 August 2009

CVE-2009-2855: Squid-cache squid improper input validation vulnerability

Squid Cache · Squid

The strListGetItem function in src/HttpHeaderTools.c in Squid 2.7 allows remote attackers to cause a denial of service via a crafted auth header with certain comma delimiters that trigger an infinite loop of calls to the strcspn function.

5.0 CVSS 2.0 Medium EPSS 34% · top 1.6% CWE-20 · Improper input validation
5.0CVSS 2.0 base score
34%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
24References
16 Jun 2026Last modified by NVD

Description

The strListGetItem function in src/HttpHeaderTools.c in Squid 2.7 allows remote attackers to cause a denial of service via a crafted auth header with certain comma delimiters that trigger an infinite loop of calls to the strcspn function.

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.

References

LinkTags
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=534982
http://bugs.debian.org/cgi-bin/bugreport.cgi?msg=31%3Bfilename=diff%3Batt=1%3Bbug=534982
http://www.openwall.com/lists/oss-security/2009/07/20/10
http://www.openwall.com/lists/oss-security/2009/08/03/3
http://www.openwall.com/lists/oss-security/2009/08/04/6
http://www.securityfocus.com/bid/36091
http://www.securitytracker.com/id?1022757
http://www.squid-cache.org/bugs/show_bug.cgi?id=2541
http://www.squid-cache.org/bugs/show_bug.cgi?id=2704 Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=518182
https://exchange.xforce.ibmcloud.com/vulnerabilities/52610
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A10592
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=534982
http://bugs.debian.org/cgi-bin/bugreport.cgi?msg=31%3Bfilename=diff%3Batt=1%3Bbug=534982
http://www.openwall.com/lists/oss-security/2009/07/20/10
http://www.openwall.com/lists/oss-security/2009/08/03/3
http://www.openwall.com/lists/oss-security/2009/08/04/6
http://www.securityfocus.com/bid/36091
http://www.securitytracker.com/id?1022757
http://www.squid-cache.org/bugs/show_bug.cgi?id=2541
http://www.squid-cache.org/bugs/show_bug.cgi?id=2704 Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=518182
https://exchange.xforce.ibmcloud.com/vulnerabilities/52610
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A10592

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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-2009-2855), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.