CVE-2026-68146 ftrace: Add global mutex to serialize trace_parser access
A race condition in the Linux kernel ftrace parser allows local attackers to corrupt state via concurrent writes, potentially causing undefined behavior or denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-68146?
CVE-2026-68146 is a vulnerability in Linux, published on 10 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
ftrace: Add global mutex to serialize trace_parser access
In ftrace, the trace_parser structure is allocated and initialized when a trace file is opened, and is subsequently used across write and release handlers to parse user input.
The affected handler paths and their specific functions are: - Open paths: ftrace_regex_open(), ftrace_graph_open() - Write paths: ftrace_regex_write(), ftrace_graph_write() - Release paths: ftrace_regex_release(), ftrace_graph_release()
If userspace opens a trace file descriptor and shares it across multiple threads, concurrent write calls will race on the parser's internal state, specifically the 'idx', 'cont', and 'buffer' fields, leading to corrupted input or undefined behavior.
Fix this by adding a global mutex, parser_lock, to serialize all access to trace_parser across write and release paths, preventing concurrent corruption of parser state.
Which versions are affected by CVE-2026-68146?
How do I fix CVE-2026-68146?
Apply the vendor's patch.
Is CVE-2026-68146 being exploited?
There is no known exploitation of CVE-2026-68146 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-68146, DEBIAN-CVE-2026-68146, GHSA-vcpv-vm68-v468, UBUNTU-CVE-2026-68146.