Cyber Resilience

CVE-2023-5380

Memory Safety in Redhat Enterprise Linux 7.0 … 9.0

Published
25 October 2023
Modified
23 June 2026
Patch / advisory
CVSS Score v3.1 4.7
Click a component to see what it means
Raw vectorCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0072 50th percentile
Risk Priority 35 floored blend · peak EPSS

Summary

CVE-2023-5380 is a medium-severity Use After Free (CWE-416) vulnerability in Redhat Enterprise Linux. Its CVSS base score is 4.7 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Application or System Exploitation (T1499.004); ranked in the top 50% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability Data

A use-after-free flaw was found in the xorg-x11-server. An X server crash may occur in a very specific and legacy configuration (a multi-screen setup with multiple protocol screens, also known as Zaphod mode) if the pointer is warped from within…

more

a window on one screen to the root window of the other screen and if the original window is destroyed followed by another window being destroyed.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1499.004 Application or System Exploitation Impact
Adversaries may exploit software vulnerabilities that can cause an application or system to crash and deny availability to users.
Why these techniques?

The use-after-free vulnerability in xorg-x11-server (CVE-2023-5380), exploitable via TigerVNC in specific multi-screen configurations, enables endpoint denial of service by crashing the X server through application exploitation.

CVEs Like This One

CVE-2026-50260Same product: Redhat Enterprise Linux
CVE-2026-50261Same product: Redhat Enterprise Linux
CVE-2026-50263Same product: Redhat Enterprise Linux
CVE-2026-50257Same product: Redhat Enterprise Linux
CVE-2023-6270Same product: Debian Debian Linux
CVE-2023-4806Same product: Fedoraproject Fedora
CVE-2026-11791Same product: Redhat Enterprise Linux
CVE-2023-4132Same product: Debian Debian Linux
CVE-2026-4271Same product: Redhat Enterprise Linux
CVE-2024-1312Same product: Fedoraproject Fedora

Affected Assets

x.org
x server
≤ 21.1.9
x.org
xwayland
≤ 23.2.2
redhat
enterprise linux
7.0, 8.0, 9.0
fedoraproject
fedora
37, 38, 39
debian
debian linux
11.0, 12.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 3 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V1.4.3

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-416

Use-after-free exploits that achieve arbitrary code execution are blocked or significantly hardened by non-executable pages and ASLR.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly incorporate memory-safety tooling and reviews that prevent most use-after-free defects.

ID.RA-01 partial match
prevents

Vulnerability identification processes can discover use-after-free issues via scanning or analysis but do not prevent their introduction.

PR.PS-02 partial match
prevents

Routine patching removes known use-after-free instances after they have been introduced in released software.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

detects

Security testing in development can detect use-after-free bugs before release.

prevents

Secure SDLC mandates memory-safety practices that reduce use-after-free defects.

prevents

Application security requirements can specify memory-management rules that mitigate use-after-free.

prevents

Secure architecture principles include memory-safety design choices that limit use-after-free exposure.

prevents

Secure coding standards directly prescribe avoidance of use-after-free patterns.

prevents

Change-management processes help ensure memory-safety fixes are deployed consistently.

References