{"id":"CVE-2026-93201","revision":"e32274ca66794410860e7dff2de2988d","records":[{"revision":"e32274ca66794410860e7dff2de2988d","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-93201","aliases":[],"title":"dm-pcache: validate seg_id fields from persistent memory","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ndm-pcache: validate seg_id fields from persistent memory\n\ncache_pos_decode(), cache_key_decode() and the last-kset branches of\ncache_replay(), the writeback worker and the GC worker take a cache\nsegment id from the cache device metadata and index cache->segments[]\nwith it without checking it against cache->n_segs. That metadata is only\nCRC-protected with a fixed public seed, so whoever supplies the cache\ndevice on a table load (CAP_SYS_ADMIN) controls the id; an out-of-range\nvalue forms a wild pcache_cache_segment pointer that is dereferenced and\nwritten through -- an out-of-bounds read and write driven by on-disk data.\n\nAdd cache_seg_id_valid() and reject an out-of-range id at each decode\nsite, failing the operation with -EIO instead of indexing past the array.\nBound the id against the initialized-segment count (cache_info.n_segs)\nrather than the physical device total. A forged cache_info.n_segs below\nseg_num otherwise leaves segments[cache_info.n_segs..seg_num) as zeroed\nstructs whose data pointer is NULL, so a forged id in that window would\nstill be dereferenced. A later patch guarantees cache_info.n_segs <=\nseg_num, and a driver-created cache sets the two equal, so valid images\nare unaffected.","state":0,"publishedAt":"2026-09-17T16:12:22.392+00:00","modifiedAt":"2026-10-19T09:07:13.558+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"drivers/md/dm-pcache/cache.c\",\n                        \"drivers/md/dm-pcache/cache.h\",\n                        \"drivers/md/dm-pcache/cache_gc.c\",\n                        \"drivers/md/dm-pcache/cache_key.c\",\n                        \"drivers/md/dm-pcache/cache_writeback.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"1d57628ff95b32d5cfa8d8f50e07690c161e9cf0\",\n                            \"lessThan\": \"96d4b275281b45aacd0f0510fa8bec85d9f7dc5a\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"1d57628ff95b32d5cfa8d8f50e07690c161e9cf0\",\n                            \"lessThan\": \"b4bf8af5e7d7db4c5e179e15017da55857761ac4\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"1d57628ff95b32d5cfa8d8f50e07690c161e9cf0\",\n                            \"lessThan\": \"90c990a68460d7b5720e5634cf650eccdf0f4098\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"drivers/md/dm-pcache/cache.c\",\n                        \"drivers/md/dm-pcache/cache.h\",\n                        \"drivers/md/dm-pcache/cache_gc.c\",\n                        \"drivers/md/dm-pcache/cache_key.c\",\n                        \"drivers/md/dm-pcache/cache_writeback.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"6.18\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"6.18\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.57\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.6\",\n                            \"lessThanOrEqual\": \"7.2.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.3\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/96d4b275281b45aacd0f0510fa8bec85d9f7dc5a","https://git.kernel.org/stable/c/b4bf8af5e7d7db4c5e179e15017da55857761ac4","https://git.kernel.org/stable/c/90c990a68460d7b5720e5634cf650eccdf0f4098"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-93201","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-93201","identifiers":["CVE-2026-93201"]},"retained":false,"historicalAffected":[]}],"coverage":[]}