SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2018-15859

Unchecked NULL pointer usage when parsing invalid atoms in ExprResolveLhs in xkbcomp/expr.c in xkbcommon before 0.8.2 could be used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file, because…

MEDIUM 5.5EPSS 0.53%

Does this matter?

Lower severity and a low EPSS score (0.53%). Track it; it rarely justifies an emergency change on its own.

Description

Unchecked NULL pointer usage when parsing invalid atoms in ExprResolveLhs in xkbcomp/expr.c in xkbcommon before 0.8.2 could be used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file, because lookup failures are mishandled.

CVSS 3.0
5.5 MEDIUMCVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS
0.53% probability · 45th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-476
Affected
xkbcommon/libxkbcommon · xkbcommon/xkbcommon · canonical/ubuntu linux
Source
cve@mitre.org
EPSS trend
0%3%5%27 October 2026: 0.53%27 October 202627 October 2026

EPSS 0.5% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.