{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-72372", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-09T03:40:39.922Z", "datePublished": "2026-08-15T05:56:07.916Z", "dateUpdated": "2026-08-17T05:43:25.401Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-17T05:43:25.401Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nafs: Fix lack of locking around modifications of net->cells_dyn_ino\n\nFix the lack of locking around modifications of net->cells_dyn_ino by\ntaking net->cells_lock exclusively. This also requires to cell to be\nremoved from net->cells_dyn_ino in afs_destroy_cell_work() rather than in\nafs_cell_destroy() as the latter runs in RCU cleanup context and sleeping\nlocks cannot be taken there." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The bug is reached only through local VFS operations on an AFS dynroot mount (getdents/readdir via afs_dynroot_readdir, lookup via afs_dynroot_lookup_cell) and cell create/destroy paths (afs_alloc_cell/afs_destroy_cell_work), not from remote AFS/RxRPC packet handling.\nAC:L - An attacker can reliably win the race by running concurrent threads that repeatedly readdir /afs while creating and expiring cells through lookups or /proc/net/afs/cells writes; syzbot and public PoCs reproduced the slab UAF within minutes without uncontrollable layout dependencies.\nPR:L - Exploitation requires only an unprivileged local user who can access a dynroot mount (typical world-readable /afs on AFS clients) or mount AFS with -o dyn inside a user namespace where CAP_SYS_ADMIN is available; real init-namespace root is not required.\nUI:N - No victim interaction is needed once dynroot is available; the attacker directly issues the readdir and cell-creation syscalls that race unsynchronized idr_alloc_cyclic, idr_remove, and idr_get_next on net->cells_dyn_ino.\nS:U - Impact is confined to kernel memory integrity and privilege boundaries within the host kernel; it does not cross VM, container, or IOMMU security scopes into a different authority.\nC:H - Concurrent idr_remove during afs_dynroot_readdir_cells leaves idr_get_next with a dangling afs_cell pointer, causing slab use-after-free reads of cell->name and cell->state (confirmed by KASAN in afs_dynroot_readdir) and enabling further kernel memory disclosure.\nI:H - IDR tree corruption and use-after-free of afs_cell objects provide attacker-influenced heap corruption primitives that can be developed into arbitrary kernel writes or control-flow hijack, not merely a benign error return.\nA:H - The race causes kernel oops/panic from corrupted IDR traversal or use-after-free during dir_emit; repeated triggering can crash or hang the system, satisfying high availability impact." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/afs/cell.c", "fs/afs/dynroot.c" ], "versions": [ { "version": "537b0105952578531f748c7fb3ce36ae9a514784", "lessThan": "4d8a2fe8847859f4fa4e9a2fa1221c9c1158e66b", "status": "affected", "versionType": "git" }, { "version": "1d0b929fc070b4115403a0a6206a0c6a62dd61f5", "lessThan": "2ffb70a8a01988046bb207b7d0af9358a8337378", "status": "affected", "versionType": "git" }, { "version": "1d0b929fc070b4115403a0a6206a0c6a62dd61f5", "lessThan": "e94f92fd56c553a8bf9421c3289e1b85c7c08857", "status": "affected", "versionType": "git" }, { "version": "1d0b929fc070b4115403a0a6206a0c6a62dd61f5", "lessThan": "55e841836c6f4646490f7b0347192b7a92d431ba", "status": "affected", "versionType": "git" }, { "version": "6.12.97", "lessThan": "6.12.101", "status": "affected", "versionType": "semver" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/afs/cell.c", "fs/afs/dynroot.c" ], "versions": [ { "version": "6.15", "status": "affected" }, { "version": "0", "lessThan": "6.15", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.101", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.40", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1.5", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.12.97", "versionEndExcluding": "6.12.101" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.15", "versionEndExcluding": "6.18.40" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.15", "versionEndExcluding": "7.1.5" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.15", "versionEndExcluding": "7.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/4d8a2fe8847859f4fa4e9a2fa1221c9c1158e66b" }, { "url": "https://git.kernel.org/stable/c/2ffb70a8a01988046bb207b7d0af9358a8337378" }, { "url": "https://git.kernel.org/stable/c/e94f92fd56c553a8bf9421c3289e1b85c7c08857" }, { "url": "https://git.kernel.org/stable/c/55e841836c6f4646490f7b0347192b7a92d431ba" } ], "title": "afs: Fix lack of locking around modifications of net->cells_dyn_ino", "x_generator": { "engine": "bippy-1.2.0" } } } }