{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2025-37952", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-04-16T04:51:23.973Z", "datePublished": "2025-05-20T16:01:47.164Z", "dateUpdated": "2026-08-05T11:58:35.992Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T11:58:35.992Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: Fix UAF in __close_file_table_ids\n\nA use-after-free is possible if one thread destroys the file\nvia __ksmbd_close_fd while another thread holds a reference to\nit. The existing checks on fp->refcount are not sufficient to\nprevent this.\n\nThe fix takes ft->lock around the section which removes the\nfile from the file table. This prevents two threads acquiring the\nsame file pointer via __close_file_table_ids, as well as the other\nfunctions which retrieve a file from the IDR and which already use\nthis same lock." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 8.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:N - ksmbd is the in-kernel SMB server; the entire path is driven by SMB2 PDUs (TREE_DISCONNECT, LOGOFF, CLOSE) arriving on TCP/445 from a remote peer. No local access is involved at any point.\nAC:L - The attacker controls both sides of the race — each SMB2 request is dispatched to the concurrent \"ksmbd-io\" workqueue, so pipelining CLOSE alongside TREE_DISCONNECT/LOGOFF on one connection (or using multichannel connections sharing one file table) reliably produces overlapping execution. The unlocked IDR walk gives a wide window, and the race can be retried indefinitely.\nPR:L - The attacker must complete SMB2 SESSION_SETUP, TREE_CONNECT and open at least one file so the session file table is populated, which needs valid (low-privilege) share credentials in a default configuration. Any ordinary share user qualifies, and on guest-mapped public shares even that requirement disappears.\nUI:N - The attacker drives the entire sequence from their own SMB connection; no action by a local user or administrator is needed.\nS:U - The corruption and its consequences are confined to the kernel's own security authority; there is no VM, IOMMU or sandbox boundary crossed.\nC:H - The freed ksmbd_file is dereferenced for fp->tcon, fp->f_ci and the fp->blocked_works list, and the attacker can reallocate the slab object via SMB2_CREATE to control those contents, turning the UAF into an arbitrary kernel-memory read primitive.\nI:H - set_close_state_blocked_works() performs `cancel_work->state = KSMBD_WORK_CLOSED` and then an indirect call `cancel_work->cancel_fn(cancel_work->cancel_argv)` using pointers read out of freed memory, and __ksmbd_close_fd() fput()s a stale struct file and double-frees the object — giving write-what-where and control-flow hijack primitives.\nA:H - Even unexploited, the double refcount decrement and double kmem_cache_free/fput corrupt the slab allocator and file refcounts, causing an immediate oops or panic that takes down the whole server." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/smb/server/vfs_cache.c" ], "versions": [ { "version": "0626e6641f6b467447c81dd7678a69c66f7746cf", "lessThan": "fec1f9e9a650e8e7011330a085c77e7bf2a08ea9", "status": "affected", "versionType": "git" }, { "version": "0626e6641f6b467447c81dd7678a69c66f7746cf", "lessThan": "9e9841e232b51171ddf3bc4ee517d5d28dc8cad6", "status": "affected", "versionType": "git" }, { "version": "0626e6641f6b467447c81dd7678a69c66f7746cf", "lessThan": "16727e442568a46d9cca69fe2595896de86e120d", "status": "affected", "versionType": "git" }, { "version": "0626e6641f6b467447c81dd7678a69c66f7746cf", "lessThan": "36991c1ccde2d5a521577c448ffe07fcccfe104d", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/smb/server/vfs_cache.c" ], "versions": [ { "version": "5.15", "status": "affected" }, { "version": "0", "lessThan": "5.15", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.91", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.29", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.14.7", "lessThanOrEqual": "6.14.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.15", "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": "5.15", "versionEndExcluding": "6.6.91" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.12.29" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.14.7" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.15" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/fec1f9e9a650e8e7011330a085c77e7bf2a08ea9" }, { "url": "https://git.kernel.org/stable/c/9e9841e232b51171ddf3bc4ee517d5d28dc8cad6" }, { "url": "https://git.kernel.org/stable/c/16727e442568a46d9cca69fe2595896de86e120d" }, { "url": "https://git.kernel.org/stable/c/36991c1ccde2d5a521577c448ffe07fcccfe104d" } ], "title": "ksmbd: Fix UAF in __close_file_table_ids", "x_generator": { "engine": "bippy-1.2.0" } } } }