Network Namespace Reference Imbalance in Linux Kernel BPF Functions

CVE-2026-74715

What is CVE-2026-74715?

A vulnerability in the Linux kernel's BPF conntrack kfuncs can lead to a network namespace reference imbalance. The opts argument can reference a shared map value, allowing operations on this value to lead to inconsistent state management. This can result in crashing issues or kernel panic due to null pointer dereferencing, especially when the reference counts for network namespaces are not properly balanced. Snapshotting the opts input fields with READ_ONCE() is crucial for maintaining stability during concurrent updates, ensuring system reliability.

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