CVE-2026-53292 Linux CVE debrief

Who should care

Linux kernel developers, Linux distribution maintainers, and users of Linux-based systems should be aware of this vulnerability. They should check their systems for the affected kernel versions and apply patches or updates as needed. Additionally, users of Linux-based systems should be cautious when handling untrusted input to prevent exploitation of this vulnerability.

Technical summary

The vulnerability is located in the pn_socket_autobind() function in the net/phonet/socket.c file of the Linux kernel. The function calls pn_socket_bind() with port 0 and checks the return value. If pn_socket_bind() returns -EINVAL, the function assumes the socket was already bound and asserts that the port is non-zero using a BUG_ON() statement. However, pn_socket_bind() also returns -EINVAL when the socket's state is not TCP_CLOSE, even if the socket has never been bound. In this case, the BUG_ON() statement triggers a kernel panic. The fix is to treat this case as a regular error and return -EINVAL to the caller.

Defensive priority

High priority should be given to patching or updating Linux kernel versions affected by this vulnerability. Linux distribution maintainers should update their kernel packages to include the fix. Users of Linux-based systems should apply patches or updates as soon as possible to prevent exploitation.

Recommended defensive actions

• Apply patches or updates to Linux kernel versions affected by this vulnerability.
• Check Linux distribution kernel packages for updates and apply them as needed.
• Monitor Linux-based systems for unusual activity that may indicate exploitation attempts.
• Consider implementing additional security measures, such as restricting access to sensitive data and services.
• Perform regular security audits and vulnerability assessments to identify potential vulnerabilities.

Evidence notes

The vulnerability was reported by syzbot and resolved by Linux kernel developers. The fix was backported to stable kernel versions. The CVE record and NVD detail provide additional information about the vulnerability.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.