CVE-2025-39689

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description The Linux kernel contains a flaw in its ftrace functionality where the reader of filter files does not allocate and copy the hash, leading to a use-after-free (UAF) condition. Specifically, the reader of set ftrace filter and set ftrace notrace keeps a pointer to filter hashes without allocating a copy, unlike the writer. This can cause issues when the global tracer hashes are updated while locks are released. Allocating and copying the hash for reading filter files, similar to the writer, resolves the UAF bugs and simplifies the code.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.