CVE-2015-6564

Publication date 24 August 2015

Last updated 6 June 2026

Ubuntu priority

Cvss 3 Severity Score

Description

Use-after-free vulnerability in the mm_answer_pam_free_ctx function in monitor.c in sshd in OpenSSH before 7.0 on non-OpenBSD platforms might allow local users to gain privileges by leveraging control of the sshd uid to send an unexpectedly early MONITOR_REQ_PAM_FREE_CTX request.

Status

Show unmaintained releases

Package	Ubuntu Release	Status
openssh	15.04 vivid	Fixed 1:6.7p1-5ubuntu1.2
	14.04 LTS trusty	Fixed 1:6.6p1-2ubuntu2.2
	12.04 LTS precise	Fixed 1:5.9p1-5ubuntu1.6

How can I get the fixes?
What do statuses mean?

Severity score breakdown

Parameter	Value
Base score	7.0 · High
Attack vector	Local
Attack complexity	High
Privileges required	Low
User interaction	None
Scope	Unchanged
Confidentiality	High
Integrity impact	High
Availability impact	High
Vector	CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

References

MITRE
NVD
Launchpad
Debian

Other references

https://anongit.mindrot.org/openssh.git/commit/?id=5e75f5198769056089fb06c4d738ab0e5abc66f7
http://www.openwall.com/lists/oss-security/2015/08/11/9
https://github.com/openssh/openssh-portable/commit/5e75f5198769056089fb06c4d738ab0e5abc66f7
http://www.openwall.com/lists/oss-security/2015/08/22/1
http://www.openssh.com/txt/release-7.0
http://seclists.org/fulldisclosure/2015/Aug/54
http://www.openwall.com/lists/oss-security/2015/08/22/1
https://www.cve.org/CVERecord?id=CVE-2015-6564