CVE-2026-64109: In the Linux kernel, the following vulnerability has been resolved: af_unix: Fix UAF read of tail->len in unix_stream_d
Summary
A use-after-free (UAF, accessing memory that has already been freed) vulnerability exists in the Linux kernel's Unix socket code, specifically in the unix_stream_data_wait() function. The function reads data from a socket queue without proper locking, allowing another thread to free that data while it's being accessed, causing a crash or potential security issue. This only affects kernels version 6.5 and later.
Solution / Mitigation
Fix the UAF by removing the read of tail->len in unix_stream_data_wait(). As explained in the source: checking tail->len is unnecessary because data is now always added to a new socket buffer (skb) rather than appended to existing ones, so the length cannot change while waiting. This fix is only suitable for kernels version 6.5 and later.
Vulnerability Details
EPSS: 0.0%
July 19, 2026
Classification
Original source: https://nvd.nist.gov/vuln/detail/CVE-2026-64109
First tracked: July 19, 2026 at 02:09 PM
Classified by LLM (prompt v3) · confidence: 95%