The flaw occurs in the MS‑NTFS filesystem driver in the Linux kernel. The bitmap size is determined at mount time and is independent from the actual cluster count on the disk. When the bitmap is larger than the volume’s cluster layout the allocator the bitmap array. Extending a file triggers this out‑of‑bounds read, which KASAN reports. This read may expose kernel memory or cause a crash; the vulnerability does not allow arbitrary code execution.

All Linux kernels that ship with the unpatched ntfs module are affected. The issue exists in any kernel version where the ntfs path includes the unpatched code, regardless of numbering. The specific versions are not listed in the advisory, so all releases prior to the The patch is included in recent kernel releases (commit 19cac7…).

The CVSS score of 4.7 indicates moderate severity. EPSS indicates an exploitation probability of less than 1%, and the vulnerability is not listed in the CISA KEV catalog, implying no publicly documented exploits. The attack vector is inferred to require local privileged access to a system that mounts a malicious NTFS volume and can modify files on it. Consequently, the risk to systems without such an attack vector is low, while systems that could be manipulated by local users face a moderate risk of kernel crash or data leakage.