CVE-2026-98415

What it actually does

Use-after-free caused by calling of_node_put() on an interrupt generator device-tree node immediately after of_parse_phandle(), then passing the dangling pointer to of_syscon_register_regmap() later in setup_cpuhp_and_cpuidle().

Why it matters to the business

Kernel instability or memory corruption on Samsung Exynos-based systems can cause crashes, denial of service, or potential local privilege escalation; low EPSS and no KEV listing indicate limited observed exploitation but still requires prompt patching within normal update cycles.

How an attack unfolds

An attacker with local access or the ability to influence device-tree parsing during CPU hotplug and cpuidle initialization triggers the path that re-uses the already-released node reference, leading to a dangling-pointer dereference inside the PMU driver.

How to fix it

Apply the upstream fix that declares intr_gen_node with __free() and removes the early of_node_put(); rebuild and deploy the corrected kernel image to all affected Samsung Exynos platforms.

How to confirm the fix worked

Confirm the corrected source contains the __free() declaration and absence of the immediate of_node_put(); verify the running kernel was built from a tree that includes the commit resolving the reference-count ordering in exynos-pmu.

Typical attack path

1. Obtain local execution or control over early boot / device-tree loading on an affected Exynos SoC
2. Trigger setup_cpuhp_and_cpuidle() so that of_parse_phandle() obtains the intr_gen_node
3. Allow the premature of_node_put() to drop the final reference
4. Force subsequent call to of_syscon_register_regmap() with the freed pointer
5. Leverage resulting use-after-free for memory corruption or crash

How to detect it

Examine kernel logs for oops or panic messages referencing exynos-pmu, of_syscon_register_regmap, or use-after-free in the soc/samsung directory; inspect boot logs around CPU hotplug and cpuidle initialization for node reference warnings.

What your security team should do

• Prioritize inclusion of the fix in the next kernel update for all Exynos-based devices
• Monitor upstream stable and distribution kernels for the merged patch
• Test the updated kernel on representative hardware to ensure CPU hotplug and cpuidle continue to function
• Review device-tree overlays or custom PMU configurations that may increase exposure