{
  "affected": [
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:14",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "details": "In the Linux kernel, the following vulnerability has been resolved:  dm-pcache: validate seg_id fields from persistent memory  cache_pos_decode(), cache_key_decode() and the last-kset branches of cache_replay(), the writeback worker and the GC worker take a cache segment id from the cache device metadata and index cache-\u003esegments[] with it without checking it against cache-\u003en_segs. That metadata is only CRC-protected with a fixed public seed, so whoever supplies the cache device on a table load (CAP_SYS_ADMIN) controls the id; an out-of-range value forms a wild pcache_cache_segment pointer that is dereferenced and written through -- an out-of-bounds read and write driven by on-disk data.  Add cache_seg_id_valid() and reject an out-of-range id at each decode site, failing the operation with -EIO instead of indexing past the array. Bound the id against the initialized-segment count (cache_info.n_segs) rather than the physical device total. A forged cache_info.n_segs below seg_num otherwise leaves segments[cache_info.n_segs..seg_num) as zeroed structs whose data pointer is NULL, so a forged id in that window would still be dereferenced. A later patch guarantees cache_info.n_segs \u003c= seg_num, and a driver-created cache sets the two equal, so valid images are unaffected.",
  "id": "DEBIAN-CVE-2026-93201",
  "modified": "2026-09-18T04:47:33.582988734Z",
  "published": "2026-09-17T17:18:16.403Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://security-tracker.debian.org/tracker/CVE-2026-93201"
    }
  ],
  "upstream": [
    "CVE-2026-93201"
  ]
}