A flaw in the Linux kernel's dm‑log subsystem causes an integer overflow when rounding a region count to the next multiple of BITS_PER_LONG. On 32‑bit architectures, if the region size is smaller than BITS_PER_LONG yet less than UINT_MAX, the rounding step sets the size to 2^32, which wraps the size_t variable back to zero before it is divided by eight. The resulting bitmap allocation is eight bytes smaller than required, and an out‑of‑bounds write occurs. The corruption is a buffer overflow that can overwrite kernel memory, potentially allowing an attacker to gain elevated privileges or crash the system.

All 32‑bit Linux kernels that have not incorporated commit c20e36b7631d to fix the dm‑log bitmap allocation are affected. This includes every distribution running an unpatched 32‑bit kernel, regardless of architecture, as the vulnerable code is part of the core kernel and used whenever dm‑log is active.

The CVSS score of 7.8 indicates a high severity vulnerability, but the EPSS score of <1% shows that exploitation is unlikely in the wild, and it is not listed in the CISA KEV catalog. The attack vector is inferred to be local or privileged, requiring an attacker to interact with the dm‑log subsystem—typically by creating or manipulating a block device that triggers the buggy bitmap allocation. No public exploit is known, but kernel memory corruption of this nature could be leveraged for privilege escalation or denial of service if an exploit were developed.