Cyber Resilience

CVE-2023-6546

Race Condition in Linux Kernel ≤ 6.5

Published
21 December 2023
Modified
06 August 2026
Patch / advisory
CVSS Score v3.1 7.0
Click a component to see what it means
Raw vectorCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0077 52th percentile
Risk Priority 53 floored blend · peak EPSS

Summary

CVE-2023-6546 is a high-severity Race Condition within a Thread (CWE-366) vulnerability in Linux Linux Kernel. Its CVSS base score is 7.0 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked in the top 48% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

A race condition was found in the GSM 0710 tty multiplexor in the Linux kernel. This issue occurs when two threads execute the GSMIOC_SETCONF ioctl on the same tty file descriptor with the gsm line discipline enabled, and can lead…

more

to a use-after-free problem on a struct gsm_dlci while restarting the gsm mux. This could allow a local unprivileged user to escalate their privileges on the system.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
T1548 Abuse Elevation Control Mechanism Privilege Escalation
Adversaries may circumvent mechanisms designed to control privilege elevation to gain higher-level permissions.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-4155Same product: Fedoraproject Fedora
CVE-2023-4133Same product: Fedoraproject Fedora
CVE-2023-3269Same product: Fedoraproject Fedora
CVE-2023-3161Same product: Fedoraproject Fedora
CVE-2023-39191Same product: Fedoraproject Fedora
CVE-2023-39198Same product: Fedoraproject Fedora
CVE-2023-39192Same product: Fedoraproject Fedora
CVE-2024-0607Same product: Fedoraproject Fedora
CVE-2023-39189Same product: Fedoraproject Fedora
CVE-2023-39193Same product: Fedoraproject Fedora

Affected Assets

linux
linux kernel
6.5 · ≤ 6.5
fedoraproject
fedora
39
redhat
enterprise linux
8.0, 9.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V10.4.2
  • V10.4.5
  • V15.1.3
  • V15.4.1

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-362

Accurate timestamps from internal clocks enable detection of race conditions by providing reliable event ordering in audit logs.

addresses: CWE-362

Coordination of concurrent security activities reduces the probability that shared resources will be accessed simultaneously without proper synchronization.

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 require synchronization primitives and concurrency analysis that prevent intra-thread race conditions.

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.

finds

Security testing can detect race conditions through concurrency and stress testing.

prevents

Secure development lifecycle includes concurrency and synchronization practices that reduce race conditions.

prevents

Application security requirements can mandate thread-safety and locking controls.

prevents

Secure architecture principles address concurrent access and resource synchronization.

prevents

Secure coding standards directly require proper synchronization primitives to prevent race conditions.

none

Change management can introduce or remove synchronization flaws during updates.

References