The atmel‑tdes crypto driver in the Linux kernel incorrectly uses dma_sync_single_for_device() to sync DMA memory before the CPU processes data produced by the device. The correct function is dma_sync_single_for_cpu(). Using the wrong direction can leave stale cache entries visible to the CPU on non‑coherent systems, causing the CPU to read outdated or incorrect data from the DMA buffer. This flaw reflects a cache‑coherency handling weakness (CWE‑821).

All publicly released Linux kernel versions that contain the unpatched atmel‑tdes driver are vulnerable. The advisory does not specify exact version numbers; any kernel build published before the fix commit is at risk, especially when run on hardware where DMA memory is not automatically coherent with the CPU.

The EPSS score is below 1% and the vulnerability is not listed in the CISA KEV catalog, indicating a very low but non‑zero likelihood of exploitation. The flaw does not provide remote code execution or privilege escalation. Exploitation would require the ability to invoke the atmel‑tdes crypto API from a privileged context (e.g., a kernel module or user program with CAP_SYS_ADMIN) and a platform that performs non‑coherent DMA, making the attack vector local with kernel access.