CVE-2025-38632
What it is
In the Linux kernel, the following vulnerability has been resolved: pinmux: fix race causing mux_owner NULL with active mux_usecount commit 5a3e85c3c397 ("pinmux: Use sequential access to access desc->pinmux data") tried to address the issue when two client of the same gpio calls pinctrl_select_state() for the same functionality, was resulting in NULL pointer issue while accessing desc->mux_owner. However, issue was not completely fixed due to the way it was handled and it can still result in the same NULL pointer. The issue occurs due to the following interleaving: cpu0 (process A) cpu1 (process B) pin_request() { pin_free() { mutex_lock() desc->mux_usecount--; //becomes 0 .. mutex_unlock() mutex_lock(desc->mux) desc->mux_usecount++; // becomes 1 desc->mux_owner = owner; mutex_unlock(desc->mux) mutex_lock(desc->mux) desc->mux_owner = NULL; mutex_unlock(desc->mux) This sequence leads to a state where the pin appears to be in use (`mux_usecount == 1`) but has no owner (`mux_owner == NULL`), which can cause NULL pointer on next pin_request on the same pin. Ensure that updates to mux_usecount and mux_owner are performed atomically under the same lock. Only clear mux_owner when mux_usecount reaches zero and no new owner has been assigned.
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of service disruption.
- Exploit odds
- 0.1% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.1% in the next 30 days (EPSS).
- Severity: 4.7 MEDIUM (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.1% · EPSS, next 30 days
- Weakness
- CWE-362 · Race condition
- Record status
- Modified
Affected
- Linux Kernel < 6.6.102
- Linux Kernel < 6.12.42
- Linux Kernel < 6.15.10
- Linux Kernel < 6.16.1
Attack profile CVSS 3.1 · 4.7
- Attack vector
- Local
- Complexity
- High
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2025-38632.md and follow it. Check whether this project is affected by CVE-2025-38632. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://git.kernel.org/stable/c/0b075c011032f88d1cfde3b45d6dcf08b44140eb
- https://git.kernel.org/stable/c/22b585cbd67d14df3b91529d1b990661c300faa9
- https://git.kernel.org/stable/c/9b2a3e7189028aa7c4d53a84364f2ea9fb209787
- https://git.kernel.org/stable/c/9ea3f6b9a67be3476e331ce51cac316c2614a564
- https://git.kernel.org/stable/c/b7bd6e3971eb7f0e34d2fdce1b18b08094e0c804
References
- https://git.kernel.org/stable/c/0b075c011032f88d1cfde3b45d6dcf08b44140eb
- https://git.kernel.org/stable/c/22b585cbd67d14df3b91529d1b990661c300faa9
- https://git.kernel.org/stable/c/8434dec94e73cad527341d6280895191d949a702
- https://git.kernel.org/stable/c/9b2a3e7189028aa7c4d53a84364f2ea9fb209787
- https://git.kernel.org/stable/c/9ea3f6b9a67be3476e331ce51cac316c2614a564
- https://git.kernel.org/stable/c/b7bd6e3971eb7f0e34d2fdce1b18b08094e0c804