CVE-2016-4556

Publication date 10 May 2016

Last updated 25 August 2025

Ubuntu priority

Cvss 3 Severity Score

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.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
squid3	16.04 LTS xenial	Fixed 3.5.12-1ubuntu7.2
	15.10 wily	Fixed 3.3.8-1ubuntu16.3
	14.04 LTS trusty	Fixed 3.3.8-1ubuntu6.8
	12.04 LTS precise	Fixed 3.1.19-1ubuntu3.12.04.7

Notes

mdeslaur

same fixes as CVE-2016-4555

Severity score breakdown

Parameter	Value
Base score	7.5 · High
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	None
Integrity impact	None
Availability impact	High
Vector	CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

Related Ubuntu Security Notices (USN)

USN-2995-1
Squid vulnerabilities
9 June 2016