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Vulnerability record · CVE-2011-4096 · published 17 November 2011

CVE-2011-4096: Squid-cache squid vulnerability

Squid Cache · Squid

The idnsGrokReply function in Squid before 3.1.16 does not properly free memory, which allows remote attackers to cause a denial of service (daemon abort) via a DNS reply containing a CNAME record that references another CNAME record that contains an empty A record.

5.0 CVSS 2.0 Medium EPSS 37% · top 1.5% CWE-399 · CWE-399
5.0CVSS 2.0 base score
37%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
22References
16 Jun 2026Last modified by NVD

Description

The idnsGrokReply function in Squid before 3.1.16 does not properly free memory, which allows remote attackers to cause a denial of service (daemon abort) via a DNS reply containing a CNAME record that references another CNAME record that contains an empty A record.

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.squid-cache.org/show_bug.cgi?id=3237#c12
http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00010.html
http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00040.html
http://secunia.com/advisories/46609 Vendor Advisory
http://secunia.com/advisories/47459
http://www.mandriva.com/security/advisories?name=MDVSA-2011:193
http://www.openwall.com/lists/oss-security/2011/10/31/5
http://www.openwall.com/lists/oss-security/2011/11/01/3
http://www.redhat.com/support/errata/RHSA-2011-1791.html
http://www.securitytracker.com/id?1026265
http://www.squid-cache.org/Versions/v3/3.1/changesets/SQUID_3_1_16.html
http://bugs.squid-cache.org/show_bug.cgi?id=3237#c12
http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00010.html
http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00040.html
http://secunia.com/advisories/46609 Vendor Advisory
http://secunia.com/advisories/47459
http://www.mandriva.com/security/advisories?name=MDVSA-2011:193
http://www.openwall.com/lists/oss-security/2011/10/31/5
http://www.openwall.com/lists/oss-security/2011/11/01/3
http://www.redhat.com/support/errata/RHSA-2011-1791.html
http://www.securitytracker.com/id?1026265
http://www.squid-cache.org/Versions/v3/3.1/changesets/SQUID_3_1_16.html

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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-2011-4096), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.