CVE-2023-53377 cifs: prevent use-after-free by freeing the cfile later

What is CVE-2023-53377?

CVE-2023-53377 is a high-severity use after free vulnerability in Linux kernel, published on 18 Sep 2025. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

In the Linux kernel, the following vulnerability has been resolved:

cifs: prevent use-after-free by freeing the cfile later

In smb2_compound_op we have a possible use-after-free which can cause hard to debug problems later on.

This was revealed during stress testing with KASAN enabled kernel. Fixing it by moving the cfile free call to a few lines below, after the usage.

Weakness: CWE-416

Which versions are affected by CVE-2023-53377?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2023-53377?

Apply the vendor's patch.

Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.

Is CVE-2023-53377 being exploited?

There is no known exploitation of CVE-2023-53377 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BELL-CVE-2023-53377, DEBIAN-CVE-2023-53377, GHSA-2h3h-p2mp-rw5q, UBUNTU-CVE-2023-53377.