CVE-2023-54076
A critical vulnerability in the Linux kernel’s SMB client could allow an attacker to trigger a use‑after‑free error, potentially leading to arbitrary code execution. The flaw occurs when the kernel fails to correctly reference SMB sessions, allowing a malicious server to free memory that the client still uses. The issue has been fixed in a kernel update.
An official fix is available, so this entry is kept for 30 days and then removed automatically.
Who is affected
Linux kernel versions that use the CIFS SMB client before the patch that fixed the session reference counting bug. Linux system administrators and users running SMB client services on affected kernels are at risk.
Real-world impact
An attacker could trigger a use‑after‑free in the SMB client, potentially executing arbitrary code with kernel privileges and compromising the entire system.
Why this severity
The CVSS score of 9.8 reflects that the vulnerability is exploitable over the network, requires no user interaction, and can lead to complete compromise of confidentiality, integrity, and availability.
What to do about it
- 01Update your Linux kernel to a version that includes the fix for CVE-2023-54076.
- 02Reboot the system to load the new kernel.
NVD-referenced vendor advisory
Timeline
- Dec 24, 2025 · Dec 24, 2025PublishedDisclosed and added to the National Vulnerability Database.
- Aug 4, 2026 · 1d agoAdvisory updatedThe NVD record was last revised.
- Aug 4, 2026 · 1d agoOfficial fix availableA vendor patch or mitigation now exists — see the remediation steps above.