CVE-2026-90422 clk: mediatek: pllfh: Fix IO remapping leak in register_pllfhs error path
A memory leak in the MediaTek PLL clock driver error path can lead to resource exhaustion and denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Not stated
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-90422?
CVE-2026-90422 is a memory corruption vulnerability in Linux, published on 17 Sep 2026.
Official description
In the Linux kernel, the following vulnerability has been resolved:
clk: mediatek: pllfh: Fix IO remapping leak in register_pllfhs error path
When mtk_clk_register_pllfhs function fails to register a PLL, it unregisters all PLLs and cleans up itself in its error path before returning, so the function callers don't need to do it.
But contrary to mtk_clk_unregister_pllfhs function, that does almost the same sequence, it does not free the IO memory mapped on fhctl node, leading to a leak.
Fix this leak by factorizing the cleanup sequence in a new private function and use it both mtk_clk_register_pllfhs and mtk_clk_unregister_pllfhs functions.
Also, change the loop index start value to avoid the -1 operation on index at each loop.
Which versions are affected by CVE-2026-90422?
How do I fix CVE-2026-90422?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-90422 being exploited?
There is no known exploitation of CVE-2026-90422 in the wild and no public exploit code.
Sources
Also known as AZL-110438, BELL-CVE-2026-90422, DEBIAN-CVE-2026-90422, GHSA-hw67-72fp-vf5f, UBUNTU-CVE-2026-90422.