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Vulnerability record · CVE-2016-3948 · published 7 April 2016

CVE-2016-3948: Squid-cache squid memory buffer overflow vulnerability

Squid Cache · Squid

Squid 3.x before 3.5.16 and 4.x before 4.0.8 improperly perform bounds checking, which allows remote attackers to cause a denial of service via a crafted HTTP response, related to Vary headers.

7.5 CVSS 3.0 High EPSS 35% · top 1.6% CWE-119 · Memory buffer overflow
7.5CVSS 3.0 base score, v2 5.0
35%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
18References
17 Jun 2026Last modified by NVD

Description

Squid 3.x before 3.5.16 and 4.x before 4.0.8 improperly perform bounds checking, which allows remote attackers to cause a denial of service via a crafted HTTP response, related to Vary headers.

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

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

References

LinkTags
http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00010.html
http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00040.html
http://lists.opensuse.org/opensuse-updates/2016-08/msg00069.html
http://rhn.redhat.com/errata/RHSA-2016-2600.html
http://www.securitytracker.com/id/1035458
http://www.squid-cache.org/Advisories/SQUID-2016_4.txt Vendor Advisory
http://www.squid-cache.org/Versions/v3/3.5/changesets/squid-3.5-14016.patch Patch
https://security.gentoo.org/glsa/201607-01
https://usn.ubuntu.com/3557-1/
http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00010.html
http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00040.html
http://lists.opensuse.org/opensuse-updates/2016-08/msg00069.html
http://rhn.redhat.com/errata/RHSA-2016-2600.html
http://www.securitytracker.com/id/1035458
http://www.squid-cache.org/Advisories/SQUID-2016_4.txt Vendor Advisory
http://www.squid-cache.org/Versions/v3/3.5/changesets/squid-3.5-14016.patch Patch
https://security.gentoo.org/glsa/201607-01
https://usn.ubuntu.com/3557-1/

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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-2016-3948), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.