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TI-2023-01317 Aliases CVE-2023-1393GHSA-gvfw-3vr2-x46g

Use after free in xorg-server

Priority LOW 36CWE-416Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 20 fixed, 1 without a fix

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat. Impact type from CWE-416 and the CVSS impact.

Summary

A flaw was found in X.Org Server Overlay Window. A Use-After-Free may lead to local privilege escalation. If a client explicitly destroys the compositor overlay window (aka COW), the Xserver would leave a dangling pointer to that window in the CompScreen structure, which will trigger a use-after-free later.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00383 32nd percentileScored 2026-11-07
Fix Partial Red Hat: 13 advisoriesRed Hat: 20 fixed, 1 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
—xorg-serverxorg-server 21.1.8—No fix listedCNA
  • xorg-server Vendor— Affected xorg-server 21.1.8 Fixed in — No fix listed CNA

CPE configurations NVD · 4

CPEVersionsRoleVendor
cpe:2.3:a:x.org:x_server:*:*:*:*:*:*:*:*before 21.1.8Vulnerablex.org
cpe:2.3:o:fedoraproject:fedora:36:*:*:*:*:*:*:*36VulnerableFedoraproject
cpe:2.3:o:fedoraproject:fedora:37:*:*:*:*:*:*:*37VulnerableFedoraproject
cpe:2.3:o:fedoraproject:fedora:38:*:*:*:*:*:*:*38VulnerableFedoraproject
  • cpe:2.3:a:x.org:x_server:*:*:*:*:*:*:*:* Versions before 21.1.8 Vulnerable ·x.org
  • cpe:2.3:o:fedoraproject:fedora:36:*:*:*:*:*:*:* Versions 36 Vulnerable ·Fedoraproject
  • cpe:2.3:o:fedoraproject:fedora:37:*:*:*:*:*:*:* Versions 37 Vulnerable ·Fedoraproject
  • cpe:2.3:o:fedoraproject:fedora:38:*:*:*:*:*:*:* Versions 38 Vulnerable ·Fedoraproject

Remediation

Red Hat 13 advisories

  • RHSA-2025:12751 Released 2025-08-04 · Red Hat rating Important
    tigervnc security update
    • Red Hat Enterprise Linux Server -EXTENSION(v. 6 ELS-EXTENSION) tigervnc-1.1.0-25.el6_10.13, tigervnc-server-1.1.0-25.el6_10.13
    • Red Hat Enterprise Linux Server Optional -EXTENSION (v. 6 ELS -EXTENSION) tigervnc-server-applet-1.1.0-25.el6_10.13, tigervnc-server-module-1.1.0-25.el6_10.13
  • RHSA-2023:6917 Released 2023-11-14 · Red Hat rating Moderate
    xorg-x11-server-Xwayland security and bug fix update
    • Red Hat Enterprise Linux AppStream (v. 8) xorg-x11-server-Xwayland-21.1.3-12.el8
  • RHSA-2023:6916 Released 2023-11-14 · Red Hat rating Moderate
    xorg-x11-server security and bug fix update
    • Red Hat CodeReady Linux Builder (v. 8) xorg-x11-server-devel-1.20.11-17.el8, xorg-x11-server-source-1.20.11-17.el8
    • Red Hat Enterprise Linux AppStream (v. 8) xorg-x11-server-1.20.11-17.el8, xorg-x11-server-Xdmx-1.20.11-17.el8, xorg-x11-server-Xephyr-1.20.11-17.el8 +4
Show 10 more Red Hat advisories
  • RHSA-2023:6340 Released 2023-11-07 · Red Hat rating Moderate
    xorg-x11-server security and bug fix update
    • Red Hat CodeReady Linux Builder (v. 9) xorg-x11-server-devel-1.20.11-19.el9, xorg-x11-server-source-1.20.11-19.el9
    • Red Hat Enterprise Linux AppStream (v. 9) xorg-x11-server-1.20.11-19.el9, xorg-x11-server-Xdmx-1.20.11-19.el9, xorg-x11-server-Xephyr-1.20.11-19.el9 +4
  • RHSA-2023:6341 Released 2023-11-07 · Red Hat rating Moderate
    xorg-x11-server-Xwayland security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 9) xorg-x11-server-Xwayland-22.1.9-2.el9
  • RHSA-2023:1594 Released 2023-04-04 · Red Hat rating Important
    tigervnc and xorg-x11-server security update
    • Red Hat Enterprise Linux Client (v. 7) tigervnc-1.8.0-25.el7_9, tigervnc-icons-1.8.0-25.el7_9, tigervnc-license-1.8.0-25.el7_9 +6
    • Red Hat Enterprise Linux Client Optional (v. 7) tigervnc-server-applet-1.8.0-25.el7_9, tigervnc-server-module-1.8.0-25.el7_9, xorg-x11-server-Xdmx-1.20.4-23.el7_9 +5
    • Red Hat Enterprise Linux ComputeNode Optional (v. 7) tigervnc-1.8.0-25.el7_9, tigervnc-icons-1.8.0-25.el7_9, tigervnc-server-1.8.0-25.el7_9 +12
    • Red Hat Enterprise Linux Server (v. 7) tigervnc-1.8.0-25.el7_9, tigervnc-icons-1.8.0-25.el7_9, tigervnc-license-1.8.0-25.el7_9 +6
    • Red Hat Enterprise Linux Server Optional (v. 7) tigervnc-server-applet-1.8.0-25.el7_9, tigervnc-server-module-1.8.0-25.el7_9, xorg-x11-server-Xdmx-1.20.4-23.el7_9 +6
    • Red Hat Enterprise Linux Workstation (v. 7) tigervnc-1.8.0-25.el7_9, tigervnc-icons-1.8.0-25.el7_9, tigervnc-license-1.8.0-25.el7_9 +6
    • Red Hat Enterprise Linux Workstation Optional (v. 7) tigervnc-server-applet-1.8.0-25.el7_9, tigervnc-server-module-1.8.0-25.el7_9, xorg-x11-server-Xdmx-1.20.4-23.el7_9 +5
  • RHSA-2023:1598 Released 2023-04-04 · Red Hat rating Important
    tigervnc security update
    • Red Hat Enterprise Linux AppStream EUS (v.8.6) tigervnc-1.12.0-6.el8_6.3, tigervnc-icons-1.12.0-6.el8_6.3, tigervnc-license-1.12.0-6.el8_6.3 +4
  • RHSA-2023:1599 Released 2023-04-04 · Red Hat rating Important
    tigervnc security update
    • Red Hat Enterprise Linux AppStream EUS (v.9.0) tigervnc-1.11.0-22.el9_0.2, tigervnc-icons-1.11.0-22.el9_0.2, tigervnc-license-1.11.0-22.el9_0.2 +4
  • RHSA-2023:1600 Released 2023-04-04 · Red Hat rating Important
    tigervnc security update
    • Red Hat Enterprise Linux AppStream E4S (v. 8.1) tigervnc-1.9.0-16.el8_1.3, tigervnc-icons-1.9.0-16.el8_1.3, tigervnc-license-1.9.0-16.el8_1.3 +4
  • RHSA-2023:1592 Released 2023-04-04 · Red Hat rating Important
    tigervnc security update
    • Red Hat Enterprise Linux AppStream (v. 9) tigervnc-1.12.0-5.el9_1.2, tigervnc-icons-1.12.0-5.el9_1.2, tigervnc-license-1.12.0-5.el9_1.2 +4
  • RHSA-2023:1551 Released 2023-04-04 · Red Hat rating Important
    tigervnc security update
    • Red Hat Enterprise Linux AppStream (v. 8) tigervnc-1.12.0-9.el8_7.3, tigervnc-icons-1.12.0-9.el8_7.3, tigervnc-license-1.12.0-9.el8_7.3 +4
  • RHSA-2023:1548 Released 2023-04-03 · Red Hat rating Important
    tigervnc security update
    • Red Hat Enterprise Linux AppStream EUS (v.8.4) tigervnc-1.11.0-8.el8_4.2, tigervnc-icons-1.11.0-8.el8_4.2, tigervnc-license-1.11.0-8.el8_4.2 +4
  • RHSA-2023:1549 Released 2023-04-03 · Red Hat rating Important
    tigervnc security update
    • Red Hat Enterprise Linux AppStream AUS (v. 8.2) tigervnc-1.9.0-15.el8_2.3, tigervnc-icons-1.9.0-15.el8_2.3, tigervnc-license-1.9.0-15.el8_2.3 +4
    • Red Hat Enterprise Linux AppStream E4S (v. 8.2) tigervnc-1.9.0-15.el8_2.3, tigervnc-icons-1.9.0-15.el8_2.3, tigervnc-license-1.9.0-15.el8_2.3 +4
    • Red Hat Enterprise Linux AppStream TUS (v. 8.2) tigervnc-1.9.0-15.el8_2.3, tigervnc-icons-1.9.0-15.el8_2.3, tigervnc-license-1.9.0-15.el8_2.3 +4

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat CodeReady Linux Builder (v. 8)Fixed RHSA-2023:6916
Red Hat CodeReady Linux Builder (v. 9)Fixed RHSA-2023:6340
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2023:1551, RHSA-2023:6916, RHSA-2023:6917
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2023:1592, RHSA-2023:6340, RHSA-2023:6341
Red Hat Enterprise Linux AppStream AUS (v. 8.2)Fixed RHSA-2023:1549
Red Hat Enterprise Linux AppStream E4S (v. 8.1)Fixed RHSA-2023:1600
Red Hat Enterprise Linux AppStream E4S (v. 8.2)Fixed RHSA-2023:1549
Red Hat Enterprise Linux AppStream EUS (v.8.4)Fixed RHSA-2023:1548
Red Hat Enterprise Linux AppStream EUS (v.8.6)Fixed RHSA-2023:1598
Red Hat Enterprise Linux AppStream EUS (v.9.0)Fixed RHSA-2023:1599
Red Hat Enterprise Linux AppStream TUS (v. 8.2)Fixed RHSA-2023:1549
Red Hat Enterprise Linux Client (v. 7)Fixed RHSA-2023:1594
Red Hat Enterprise Linux Client Optional (v. 7)Fixed RHSA-2023:1594
Red Hat Enterprise Linux ComputeNode Optional (v. 7)Fixed RHSA-2023:1594
Red Hat Enterprise Linux Server (v. 7)Fixed RHSA-2023:1594
Red Hat Enterprise Linux Server -EXTENSION(v. 6 ELS-EXTENSION)Fixed RHSA-2025:12751
Red Hat Enterprise Linux Server Optional (v. 7)Fixed RHSA-2023:1594
Red Hat Enterprise Linux Server Optional -EXTENSION (v. 6 ELS -EXTENSION)Fixed RHSA-2025:12751
Red Hat Enterprise Linux Workstation (v. 7)Fixed RHSA-2023:1594
Red Hat Enterprise Linux Workstation Optional (v. 7)Fixed RHSA-2023:1594

Timeline

  1. 2026-10-02 Threatist record created from CVE-2023-1393
  2. 2026-10-03 Alias added: GHSA-gvfw-3vr2-x46g

References

Patch 1

Advisory 10

Sources

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