Networking Vulnerability in Linux Kernel Affecting Phonet Protocol

CVE-2026-64177

What is CVE-2026-64177?

A vulnerability has been identified in the Linux Kernel's Phonet Protocol, where improper handling of locks can lead to inconsistent lock states. This occurs when packets are processed from different contexts (softirq and process) without properly disabling bottom halves (BH). As a result, this can lead to potential self-deadlocks if a softirq on the same CPU attempts to access the child socket while its lock is held with BH enabled. The vulnerability has been mitigated by wrapping relevant socket reception calls with local_bh_disable() and local_bh_enable() to ensure that locks are consistently managed.

References