CVE-2015-6563

Publication date 24 August 2015

Last updated 6 June 2026

Ubuntu priority

Cvss 3 Severity Score

Description

The monitor component in sshd in OpenSSH before 7.0 on non-OpenBSD platforms accepts extraneous username data in MONITOR_REQ_PAM_INIT_CTX requests, which allows local users to conduct impersonation attacks by leveraging any SSH login access in conjunction with control of the sshd uid to send a crafted MONITOR_REQ_PWNAM request, related to monitor.c and monitor_wrap.c.

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	6.4 · Medium
Attack vector	Local
Attack complexity	High
Privileges required	High
User interaction	None
Scope	Unchanged
Confidentiality	High
Integrity impact	High
Availability impact	High
Vector	CVSS:3.1/AV:L/AC:H/PR:H/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=d4697fe9a28dab7255c60433e4dd23cf7fce8a8b
http://www.openwall.com/lists/oss-security/2015/08/11/9
https://github.com/openssh/openssh-portable/commit/d4697fe9a28dab7255c60433e4dd23cf7fce8a8b
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
https://www.cve.org/CVERecord?id=CVE-2015-6563