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TI-2018-11308 Aliases CVE-2018-15862GHSA-qw38-vjfp-wm54

Unchecked NULL pointer usage in LookupModMask in xkbcomp/expr.c in xkbcommon before 0.8.2…

Priority LOW 25CWE-476Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 3.0 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-476.

Summary

Unchecked NULL pointer usage in LookupModMask 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 with invalid virtual modifiers.

Why it matters now

EPSS 0.00433 37th percentileScored 2026-11-07
Fix Fixed Red Hat: 1 advisory

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 5

CPEVersionsRoleVendor
cpe:2.3:a:xkbcommon:libxkbcommon:*:*:*:*:*:*:*:*up to 0.8.1VulnerableXkbcommon
cpe:2.3:a:xkbcommon:xkbcommon:*:*:*:*:*:*:*:*up to 0.8.1VulnerableXkbcommon
cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*14.04VulnerableCanonical
cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*16.04VulnerableCanonical
cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*18.04VulnerableCanonical
  • cpe:2.3:a:xkbcommon:libxkbcommon:*:*:*:*:*:*:*:* Versions up to 0.8.1 Vulnerable ·Xkbcommon
  • cpe:2.3:a:xkbcommon:xkbcommon:*:*:*:*:*:*:*:* Versions up to 0.8.1 Vulnerable ·Xkbcommon
  • cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:* Versions 14.04 Vulnerable ·Canonical
  • cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:* Versions 16.04 Vulnerable ·Canonical
  • cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:* Versions 18.04 Vulnerable ·Canonical

Remediation

Red Hat 1 advisory

  • RHSA-2019:2079 Released 2019-08-06 · Red Hat rating Moderate
    Xorg security and bug fix update
    • Red Hat Enterprise Linux Client (v. 7) gdm-1:3.28.2-16.el7, libX11-1.6.7-2.el7, libX11-common-1.6.7-2.el7 +10
    • Red Hat Enterprise Linux Client Optional (v. 7) gdm-devel-1:3.28.2-16.el7, gdm-pam-extensions-devel-1:3.28.2-16.el7, libxkbcommon-devel-0.7.1-3.el7 +8
    • Red Hat Enterprise Linux ComputeNode (v. 7) libX11-1.6.7-2.el7, libX11-common-1.6.7-2.el7, libxkbcommon-0.7.1-3.el7
    • Red Hat Enterprise Linux ComputeNode Optional (v. 7) gdm-1:3.28.2-16.el7, gdm-devel-1:3.28.2-16.el7, gdm-pam-extensions-devel-1:3.28.2-16.el7 +16
    • Red Hat Enterprise Linux Server (v. 7) gdm-1:3.28.2-16.el7, gdm-1:3.28.2-16.el7.ppc, libX11-1.6.7-2.el7 +21
    • Red Hat Enterprise Linux Server Optional (v. 7) gdm-devel-1:3.28.2-16.el7, gdm-devel-1:3.28.2-16.el7.ppc, gdm-pam-extensions-devel-1:3.28.2-16.el7 +12
    • Red Hat Enterprise Linux Workstation (v. 7) gdm-1:3.28.2-16.el7, libX11-1.6.7-2.el7, libX11-common-1.6.7-2.el7 +13
    • Red Hat Enterprise Linux Workstation Optional (v. 7) gdm-devel-1:3.28.2-16.el7, gdm-pam-extensions-devel-1:3.28.2-16.el7, libxkbcommon-x11-devel-0.7.1-3.el7 +7

Vendor assessments

Red Hat

Red Hat rating: Low. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux Client (v. 7)Fixed RHSA-2019:2079
Red Hat Enterprise Linux Client Optional (v. 7)Fixed RHSA-2019:2079
Red Hat Enterprise Linux ComputeNode (v. 7)Fixed RHSA-2019:2079
Red Hat Enterprise Linux ComputeNode Optional (v. 7)Fixed RHSA-2019:2079
Red Hat Enterprise Linux Server (v. 7)Fixed RHSA-2019:2079
Red Hat Enterprise Linux Server Optional (v. 7)Fixed RHSA-2019:2079
Red Hat Enterprise Linux Workstation (v. 7)Fixed RHSA-2019:2079
Red Hat Enterprise Linux Workstation Optional (v. 7)Fixed RHSA-2019:2079
Not affected: 1 product
  • Red Hat Enterprise Linux 8

Timeline

  1. 2026-10-02 Threatist record created from CVE-2018-15862
  2. 2026-10-03 Alias added: GHSA-qw38-vjfp-wm54

References

Patch 2

Advisory 4

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences