CVE-2016-0736

Publication date 22 December 2016

Last updated 25 August 2025

Ubuntu priority

Cvss 3 Severity Score

Description

In Apache HTTP Server versions 2.4.0 to 2.4.23, mod_session_crypto was encrypting its data/cookie using the configured ciphers with possibly either CBC or ECB modes of operation (AES256-CBC by default), hence no selectable or builtin authenticated encryption. This made it vulnerable to padding oracle attacks, particularly with CBC.

Status

Show unmaintained releases

Package	Ubuntu Release	Status
apache2	17.04 zesty	Not affected
	16.10 yakkety	Fixed 2.4.18-2ubuntu4.1
	16.04 LTS xenial	Fixed 2.4.18-2ubuntu3.2
	14.04 LTS trusty	Fixed 2.4.7-1ubuntu4.15
	12.04 LTS precise	Not affected

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
apache2	Upstream: https://svn.apache.org/viewvc?view=revision&revision=1772812 Upstream: https://svn.apache.org/viewvc?view=revision&revision=1772925

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	High
Integrity impact	None
Availability impact	None
Vector	CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

References

Related Ubuntu Security Notices (USN)

USN-3279-1
Apache HTTP Server vulnerabilities
9 May 2017