Impact
This kernel bug introduces a use‑after‑free that occurs when the ACPI EC install handler fails on reduced‑hardware platforms. The freed EC context remains registered with ACPICA and later AML evaluations that read EC OpRegion fields call the stale handler, corrupting kernel memory. The resulting memory corruption can allow an attacker with local access to influence kernel behaviour and possibly execute arbitrary code. The weakness is a classic use‑after‑free, classified as CWE‑825.
Affected Systems
The flaw affects all Linux kernel versions that contain the unpatched ACPI EC driver code. It is relevant for systems with ACPI support for embedded controllers, such as battery, thermal, and backlight OpRegions, that also use reduced‑hardware EC configurations (where the EC GPE is negative). The vulnerability is present regardless of the distribution or vendor, as it is a kernel source code defect shipped with upstream. Anyone running an unpatched kernel that uses ACPI EC on a platform that defers the EC probe is potentially impacted.
Risk and Exploitability
The CVSS score of 5.8 indicates moderate severity. No EPSS score is available, and the vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog, suggesting limited public exploitation at this point. The likely attack path requires local, unprivileged access to read a sysfs file that triggers an ACPI read on an EC OpRegion. While the vulnerability could be leveraged for privilege escalation or system instability, its exploitation is more likely to cause memory corruption or kernel crashes rather than immediate remote code execution. Consequently, patching remains the most effective countermeasure.
OpenCVE Enrichment