CVE-2023-1872 Use-after-free in Linux kernel's io_uring subsystem

What is CVE-2023-1872?

CVE-2023-1872 is a high-severity use after free vulnerability in Debian Debian Linux, published on 12 Apr 2023. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

A use-after-free vulnerability in the Linux Kernel io_uring system can be exploited to achieve local privilege escalation.

The io_file_get_fixed function lacks the presence of ctx->uring_lock which can lead to a Use-After-Free vulnerability due a race condition with fixed files getting unregistered.

We recommend upgrading past commit da24142b1ef9fd5d36b76e36bab328a5b27523e8.

Weakness: CWE-416

Which versions are affected by CVE-2023-1872?

It affects 2 products.

Products include Debian Debian Linux, Linux kernel.

How do I fix CVE-2023-1872?

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-2023-1872 being exploited?

There is no known exploitation of CVE-2023-1872 in the wild and no public exploit code.

Other vulnerabilities in Debian Debian Linux

• CVE-2015-3306 ProFTPD Improper Access Control Exploited Critical 10.0
• CVE-2025-49113 RoundCube Webmail Deserialization of Untrusted Data Exploited Critical 9.9
• CVE-2026-24061 GNU InetUtils Argument Injection Exploited Critical 9.8
• CVE-2025-39682 Linux Kernel Improper Check for Unusual or Exceptional Conditions Exploited Critical 9.8
• CVE-2024-9680 Mozilla Firefox Use-After-Free Exploited Critical 9.8

All Debian Debian Linux vulnerabilities

Sources

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

Also known as AZL-26167, DEBIAN-CVE-2023-1872, GHSA-jhw6-rjph-429f, UBUNTU-CVE-2023-1872.