CVE-2017-5551

MEDIUM

Linux kernel <4.9.6 - Privilege Escalation

Title source: llm

Description

The simple_set_acl function in fs/posix_acl.c in the Linux kernel before 4.9.6 preserves the setgid bit during a setxattr call involving a tmpfs filesystem, which allows local users to gain group privileges by leveraging the existence of a setgid program with restrictions on execute permissions. NOTE: this vulnerability exists because of an incomplete fix for CVE-2016-7097.

References (8)

[Issue Tracking, Patch, Third Party Advisory] http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=497de07d89c1410d76a15bec2bb41f24a2a89f31

[Release Notes, Vendor Advisory] http://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.9.6

[Mailing List, Patch, Third Party Advisory] http://www.openwall.com/lists/oss-security/2017/01/21/3

[Third Party Advisory, VDB Entry] http://www.securityfocus.com/bid/95717

[Third Party Advisory, VDB Entry] http://www.securitytracker.com/id/1038053

[Issue Tracking, Patch] https://bugzilla.redhat.com/show_bug.cgi?id=1416126

[Issue Tracking, Patch, Third Party Advisory] https://github.com/torvalds/linux/commit/497de07d89c1410d76a15bec2bb41f24a2a89f31

View Patch ZIP pw:eip

[Third Party Advisory] http://www.debian.org/security/2017/dsa-3791

Scores

CVSS v3 4.4

EPSS 0.0006

EPSS Percentile 19.7%

Attack Vector LOCAL

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

Classification

Status published

Affected Products (2)

linux/linux_kernel < 4.9.5

n/a/n/a

Timeline

Published Feb 06, 2017

Tracked Since Feb 18, 2026