CVE-2026-90126 rtc: pcf8563: fix clock provider leak on unbind
A memory leak in the PCF8563 RTC driver allows local attackers to exhaust kernel memory via repeated device unbinding, causing denial of service.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-90126?
CVE-2026-90126 is a memory corruption vulnerability in Linux, published on 17 Sep 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:
rtc: pcf8563: fix clock provider leak on unbind
pcf8563_clkout_register_clk() registers the CLKOUT clock provider with of_clk_add_provider(), but nothing ever unwinds it: there is no of_clk_del_provider() call and the driver has no remove callback. Each of_clk_add_provider() allocates a struct of_clk_provider, takes a reference on the OF node and adds an entry to the global of_clk_providers list, none of which is released when the device is unbound. Every bind/unbind (or module reload) therefore leaks a provider structure and an of_node reference.
The clock itself is already device-managed (devm_clk_register()); only the provider registration was not. Use devm_of_clk_add_hw_provider() so the provider is removed automatically on unbind. Tie it to the parent i2c device, whose OF node carries the #clock-cells and clock-output-names properties (the RTC class device has no OF node of its own).
Which versions are affected by CVE-2026-90126?
How do I fix CVE-2026-90126?
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-2026-90126 being exploited?
There is no known exploitation of CVE-2026-90126 in the wild and no public exploit code.
Sources
Also known as AZL-102510, BELL-CVE-2026-90126, DEBIAN-CVE-2026-90126, GHSA-7jrh-4gfg-rh69, UBUNTU-CVE-2026-90126.