In the Linux kernel, a use‑after‑free bug was discovered in the fore200e ATM driver. When a PCA‑200E or SBA‑200E adapter is detached, the driver structure is freed while an associated tasklet may still be scheduled or running. The tasklet then accesses the freed memory, leading to undefined behaviour. This flaw corresponds to a use‑after‑free (CWE‑416) vulnerability, which can potentially be exploited to alter kernel memory or crash the system, effectively allowing privilege escalation or denial of service.

The vulnerability affects all Linux kernel builds that include the fore200e driver for the PCA‑200E and SBA‑200E adapters. The specific kernel versions are not listed in the advisory, so any affected release prior to the fix may be impacted. Systems that employ the fore200e driver and allow dynamic removal of the hardware are at risk.

Exploit requires a local privileged user capable of removing the PCA‑200E or SBA‑200E adapter while the kernel is handling I/O, making the attack vector a local user attack. The CVSS score of 7.5 reflects a high severity vulnerability, and an EPSS score of < 1% indicates a low probability of exploitation in the wild. The vulnerability is not listed in CISA’s KEV catalog, suggesting no known active exploitation campaigns. Nonetheless, potential for kernel crash or arbitrary code execution warrants rapid remediation.