CVE-2015-4177

MEDIUM

Description

The collect_mounts function in fs/namespace.c in the Linux kernel before 4.0.5 does not properly consider that it may execute after a path has been unmounted, which allows local users to cause a denial of service (system crash) by leveraging user-namespace root access for an MNT_DETACH umount2 system call.

References

http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=cd4a40174b71acd021877341684d8bb1dc8ea4ae

http://openwall.com/lists/oss-security/2015/05/29/10

http://openwall.com/lists/oss-security/2015/05/29/5

http://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.0.5

http://www.openwall.com/lists/oss-security/2015/06/04/5

https://bugzilla.redhat.com/show_bug.cgi?id=1248486

https://github.com/torvalds/linux/commit/cd4a40174b71acd021877341684d8bb1dc8ea4ae

Details

Source: MITRE

Published: 2016-05-02

Updated: 2016-05-06

Risk Information

CVSS v2.0

Base Score: 4.9

Vector: AV:L/AC:L/Au:N/C:N/I:N/A:C

Impact Score: 6.9

Exploitability Score: 3.9

Severity: MEDIUM

CVSS v3.0

Base Score: 5.5

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Impact Score: 3.6

Exploitability Score: 1.8

Severity: MEDIUM