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TI-2017-08976 Aliases CVE-2017-12186GHSA-5m98-6wwr-hv6v

Improper input validation in x.org xorg-x11-server

Priority MEDIUM 49CWE-391Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 3 without a fix

Attack profile from CVSS 3.0 · NVD. Fix status from CNA and Red Hat.

Summary

xorg-x11-server before 1.19.5 was missing length validation in X-Resource extension allowing malicious X client to cause X server to crash or possibly execute arbitrary code.

Why it matters now

EPSS 0.04302 91st percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Partial xorg-x11-server (The X.Org Foundation): 1.19.5Red Hat: 3 without a fix

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
x.orgxorg-x11-serverbefore 1.19.51.19.5Patch availableCNA
  • xorg-x11-server Vendorx.org Affected before 1.19.5 Fixed in 1.19.5 Patch available CNA

CPE configurations NVD · 3

CPEVersionsRoleVendor
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*8.0VulnerableDebian
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*9.0VulnerableDebian
cpe:2.3:a:x.org:x_server:*:*:*:*:*:*:*:*before 1.19.5Vulnerablex.org
  • cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:* Versions 8.0 Vulnerable ·Debian
  • cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* Versions 9.0 Vulnerable ·Debian
  • cpe:2.3:a:x.org:x_server:*:*:*:*:*:*:*:* Versions before 1.19.5 Vulnerable ·x.org

Remediation

  • Fix · CNA xorg-x11-server (The X.Org Foundation) Fixed in 1.19.5

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Advisory ·

    The X.Org Foundation xorg-x11-server — DSA-4000

    11 records Highest priority Priority MEDIUM 11 MEDIUM

    Other records, highest priority first

    • TI-2017-08974 Improper input validation in x.org xorg-x11-serverPriority MEDIUM 49
    • TI-2017-08973 Improper input validation in x.org xorg-x11-serverPriority MEDIUM 49
    • TI-2017-08972 Improper input validation in x.org xorg-x11-serverPriority MEDIUM 49

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 5AffectedNo fix planned: Will not fix
Red Hat Enterprise Linux 6AffectedNo fix planned: Will not fix
Red Hat Enterprise Linux 7AffectedNo fix planned: Will not fix
Not affected: 1 product
  • Red Hat Enterprise Linux 9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2017-12186
  2. 2026-10-03 Alias added: GHSA-5m98-6wwr-hv6v

References

  • TI-2018-10528 A flaw was found in xorg-x11-server before 1.20.3. CVSS 3.0MEDIUM 6.6
  • TI-2017-08975 xorg-x11-server before 1.19.5 was missing length validation in MIT-SCREEN-SAVER extension… CVSS 3.0CRITICAL 9.8
  • TI-2017-08974 Improper input validation in x.org xorg-x11-server CVSS 3.0CRITICAL 9.8
  • TI-2017-08973 Improper input validation in x.org xorg-x11-server CVSS 3.0CRITICAL 9.8
  • TI-2017-08972 Improper input validation in x.org xorg-x11-server CVSS 3.0CRITICAL 9.8
  • TI-2017-08971 Improper input validation in x.org xorg-x11-server CVSS 3.0CRITICAL 9.8
See all 96 →

Sources