CVE-2026-80962

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

dm-pcache: validate geometry fields from on-disk cache_info

cache_segs_init() iterates cache_info->n_segs times indexing

cache->segments[], which is sized to the cache device geometry, and

get_seg_id() takes each segment id from the on-media cache_info and the

per-segment next_seg link. Both come from cache device metadata that is

only CRC-protected with a fixed public seed, so whoever supplies the

cache device on a table load (CAP_SYS_ADMIN) controls them: an oversized

n_segs or an out-of-range id drives an out-of-bounds access of

cache->segments[] and a wild CACHE_DEV_SEGMENT() pointer into the device

mapping -- an out-of-bounds read and write from on-disk data.

Reject an n_segs that exceeds the device segment count and a segment id

that is out of range before either is used. Valid metadata is unaffected.

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References