A defect in the Linux kernel caused the dma_unmap_sg() function to be invoked with a count of scatter‑gather entries (nents) that did not match the original dma_map_sg() call. This mismatch can lead to improper unmapping of DMA buffers, resulting in memory corruption or kernel crashes. The vulnerability is a state inconsistency that may compromise the integrity and availability of the system.

All Linux kernel builds prior to the application of the patch are affected. This includes the mainline 6.19 series, all release candidates from rc1 through rc6, and any earlier stable releases that have not been updated to a fixed kernel. The vulnerability is not limited to a particular distribution but applies to any system running an unpatched kernel where the DMA unmap routine is exercised.

The CVSS score of 5.5 indicates moderate severity, and the EPSS score of less than 1% implies a very low likelihood of exploitation in the wild. The vulnerability is not listed in the CISA KEV catalog, and no public exploit has been reported. Exploiting this flaw would require privileged kernel access or a preceding vulnerability that allows DMA operation manipulation, making the attack vector non‑public and largely theoretical for most environments.