{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-98451", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:25:14.350Z", "datePublished": "2026-10-18T15:15:01.473Z", "dateUpdated": "2026-10-24T14:08:53.021Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-24T14:08:53.021Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: use finish_no_open() for non-regular inodes\n\nAn O_CREAT open can find an existing symlink or another non-regular\ninode. cifs_atomic_open() calls finish_open() on it and attaches a\ncifsFileInfo. Symlink inodes have no CIFS release operation, so the\ndentry reference held by cifsFileInfo is leaked. FMODE_OPENED also\nprevents the VFS from following the symlink.\n\nTrack whether cifs_do_create() returned an open server handle. For\nnon-regular inodes, close the handle if present, remove the pending\nopen, and call finish_no_open() so the VFS can continue the lookup.\nDo not set FMODE_CREATED unless a regular file was opened. For\nO_NOFOLLOW with __O_REGULAR, return -ELOOP before the VFS's\n-EFTYPE check.\n\nDefer closing a legacy POSIX handle on a non-regular inode until\nafter inode lookup. This avoids closing it again if lookup fails." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H", "baseScore": 8.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:N - `openat(O_CREAT)` reaches `cifs_atomic_open()` and `cifs_do_create()`; a remote SMB2 server can return a CREATE/reparse response identifying the object as `IO_REPARSE_TAG_LX_FIFO`, so the causative inode type arrives over routable SMB.\nAC:L - The server can return a FIFO for any fresh, uncached requested name; after the victim's O_CREAT, `finish_open()` and `cifs_new_fileinfo()` deterministically create the type confusion without a race or an uncontrollable precondition.\nPR:N - A malicious SMB endpoint needs no account or capability on the client; the SMB session authenticates the victim outward to the server, which directly controls the CREATE and reparse responses.\nUI:R - The remote server cannot initiate `cifs_atomic_open()` itself; a victim must mount or access its share and issue an O_CREAT open, after which the server can substitute the non-regular inode response.\nS:U - The confused `cifsFileInfo` and resulting pipe operations execute within the vulnerable client's kernel security authority and do not cross a VM, IOMMU, or other security boundary.\nC:H - `cifs_set_ops()` installs `pipefifo_fops`, but `finish_open(..., generic_file_open)` skips `fifo_open()` and `cifs_new_fileinfo()` puts a `cifsFileInfo` in `private_data`; `fifo_pipe_read()` then treats its fields as pipe buffers and pages, creating disclosure-capable type confusion.\nI:H - `pipe_release()` and `pipe_resize_ring()` treat the `cifsFileInfo` as `pipe_inode_info`, modifying fake mutex, counter, waitqueue, and buffer-pointer fields and potentially freeing the misinterpreted `pipe->bufs`, providing kernel-memory corruption primitives.\nA:H - Closing the returned FIFO fd invokes `pipe_release()` on the `cifsFileInfo`; locking its list pointers as a pipe mutex and accessing fake pipe state can immediately oops or hang the kernel, beyond the separate symlink reference leak." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/smb/client/dir.c" ], "versions": [ { "version": "d2c127197dfc0b2bae62a52e1e0d3e3ff493919e", "lessThan": "045532f920d86dd76600b635f9756e5fd671ddfc", "status": "affected", "versionType": "git" }, { "version": "d2c127197dfc0b2bae62a52e1e0d3e3ff493919e", "lessThan": "ed03d547598c92a036f20e89156540995cac889a", "status": "affected", "versionType": "git" }, { "version": "d2c127197dfc0b2bae62a52e1e0d3e3ff493919e", "lessThan": "70a7918fda54a06d836acc91eb9a3c7e860fe0a0", "status": "affected", "versionType": "git" }, { "version": "d2c127197dfc0b2bae62a52e1e0d3e3ff493919e", "lessThan": "3c07deb26273155c180aedfd9041ab58015d2521", "status": "affected", "versionType": "git" }, { "version": "d2c127197dfc0b2bae62a52e1e0d3e3ff493919e", "lessThan": "e66cf1625ec4a3fe68346119f371def713fd0a4d", "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/client/dir.c" ], "versions": [ { "version": "3.6", "status": "affected" }, { "version": "0", "lessThan": "3.6", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.160", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.113", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.56", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.9", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.3", "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": "3.6", "versionEndExcluding": "6.6.160" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.6", "versionEndExcluding": "6.12.113" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.6", "versionEndExcluding": "6.18.56" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.6", "versionEndExcluding": "7.2.9" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.6", "versionEndExcluding": "7.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/045532f920d86dd76600b635f9756e5fd671ddfc" }, { "url": "https://git.kernel.org/stable/c/ed03d547598c92a036f20e89156540995cac889a" }, { "url": "https://git.kernel.org/stable/c/70a7918fda54a06d836acc91eb9a3c7e860fe0a0" }, { "url": "https://git.kernel.org/stable/c/3c07deb26273155c180aedfd9041ab58015d2521" }, { "url": "https://git.kernel.org/stable/c/e66cf1625ec4a3fe68346119f371def713fd0a4d" } ], "title": "smb: client: use finish_no_open() for non-regular inodes", "x_generator": { "engine": "bippy-1.2.0" } } } }