The Atmel SHA-204a cryptographic driver in the Linux kernel contains an out‑of‑memory handling bug. If a memory allocation fails, the driver does not decrement the internal TFM count, which can lead to a leak of that counter and cause future read operations to block. The defect does not expose user data but can degrade system availability by stalling cryptographic operations.

All Linux kernel builds that include the Atmel SHA-204a driver before the patch are affected. The driver is part of the default kernel tree, so any distribution or custom kernel that compiles this component is vulnerable. No specific version numbers are listed, so treat all pre‑patch releases as at risk.

The EPSS score is not available and the vulnerability is not listed in the KEV catalog, suggesting limited exploitation. Exploitation would require triggering an out‑of‑memory condition within the kernel—a scenario typically confined to privileged or local contexts with constrained memory. The impact is primarily an availability issue; the likelihood of successful exploitation in the wild is considered low, but a successful trigger could reduce system responsiveness.