CVE-2016-4556

Severity: high (CVSS 7.5 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 23.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2016-05-10 · updated 2026-06-17

Description

Double free vulnerability in Esi.cc in Squid 3.x before 3.5.18 and 4.x before 4.0.10 allows remote servers to cause a denial of service (crash) via a crafted Edge Side Includes (ESI) response.

Affected products

Canonical Ubuntu Linux: 12.04, 14.04, 15.10, 16.04
Oracle Corporation Oracle Linux: 6, 7
Squid: 3.0, 3.1, 3.1.0.1, 3.1.0.2, 3.1.0.3, 3.1.0.4 (+136)

References

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://www.debian.org/security/2016/dsa-3625
http://www.openwall.com/lists/oss-security/2016/05/06/3
http://www.openwall.com/lists/oss-security/2016/05/06/5
http://www.oracle.com/technetwork/topics/security/linuxbulletinapr2016-2952096.html
http://www.securitytracker.com/id/1035770
http://www.squid-cache.org/Advisories/SQUID-2016_9.txt
http://www.squid-cache.org/Versions/v3/3.4/changesets/SQUID-2016_9.patch
http://www.squid-cache.org/Versions/v3/3.5/changesets/SQUID-2016_9.patch
http://www.ubuntu.com/usn/USN-2995-1

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