CVE-2018-1095 Information

Description

The ext4_xattr_check_entries function in fs/ext4/xattr.c in the Linux kernel through 4.15.15 does not properly validate xattr sizes which causes misinterpretation of a size as an error code and consequently allows attackers to cause a denial of service (get_acl NULL pointer dereference and system crash) via a crafted ext4 image.

CVSS Vector

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

Reference

http://openwall.com/lists/oss-security/2018/03/29/1 https://access.redhat.com/errata/RHSA-2018:2948 https://bugzilla.kernel.org/show_bug.cgi?id=199185 https://bugzilla.redhat.com/show_bug.cgi?id=1560793 https://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4.git/commit/?id=ce3fd194fcc6fbdc00ce095a852f22df97baa401 https://usn.ubuntu.com/3695-1/ https://usn.ubuntu.com/3695-2/

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

REQUIRED

Confidentiality Impact

UNCHANGED

Integrity Impact

NONE

Availability Impact

NONE

Base Score

HIGH

Base Severity

5.5