CVE-2026-99233
In the Linux kernel, the following vulnerability has been resolved: tracing/histograms: Verify event_call identity when updating synth_event refcount In event_…
Impact
In the Linux kernel, the following vulnerability has been resolved: tracing/histograms: Verify event_call identity when updating synth_event refcount In event_hist_trigger_parse() and hist_unreg_all(), the histogram registration and unregistration paths look up find_synth_event() using trace_event_name(file->event_call) and adjust se->ref if a match is found. Because find_synth_event() only compares the event basename, registering or removing a histogram on a non-synthetic trace event whose basename matches a synthetic event erroneously modifies the synthetic event's reference count. If a histogram is registered on the non-synthetic event before the synthetic event is created and removed afterwards, se->ref is decremented without a matching increment, allowing the synthetic event to be freed while an active histogram action still holds a pointer to it. Introduce find_synth_event_call() to verify that &se->call matches file->event_call before adjusting se->ref.
An attacker can exploit this with local access to the system, with a regular user account, without any action by a user. If it succeeds: high risk of data being read, high risk of data or systems being changed, high risk of outages.
Affected products · Linux
| Product | Affected versions |
|---|---|
| Linux | from 4b147936fa509650beaf638b331573c23ba4d609 before 381f543ed35c434d5b707369aa5dcd69ecf440af from 4b147936fa509650beaf638b331573c23ba4d609 before 4472579bd1c83708b6fe623c870cdf728e947205 from 4b147936fa509650beaf638b331573c23ba4d609 before 23b4106e8b35823acc79e206c7745f55b9cfd78b from 4b147936fa509650beaf638b331573c23ba4d609 before 06e816bed499fe47f39f12044382cc5d064485fb from 4b147936fa509650beaf638b331573c23ba4d609 before 5597bb8db6855fcb97a67196d227fea359bcd81c from 4b147936fa509650beaf638b331573c23ba4d609 before cf4e31d5da80fae4c9cdbe7af55b7c3ad213f0e4 |
References
- NVD record
- CVE.org record
- GitHub advisory
- https://git.kernel.org/stable/c/381f543ed35c434d5b707369aa5dcd69ecf440af
- https://git.kernel.org/stable/c/4472579bd1c83708b6fe623c870cdf728e947205
- https://git.kernel.org/stable/c/23b4106e8b35823acc79e206c7745f55b9cfd78b
- https://git.kernel.org/stable/c/06e816bed499fe47f39f12044382cc5d064485fb
- https://git.kernel.org/stable/c/5597bb8db6855fcb97a67196d227fea359bcd81c
- https://git.kernel.org/stable/c/cf4e31d5da80fae4c9cdbe7af55b7c3ad213f0e4
- https://github.com/advisories/GHSA-hqr3-rh3c-f6xh
- https://nvd.nist.gov/vuln/detail/CVE-2026-99233
- https://git.kernel.org/stable/c/3403d9bb27ebc3572bd048620746b4414e073bf9