{"id":"CVE-2026-97561","state":"PUBLISHED","title":"smb: client: honor forceuid/forcegid when mapping SIDs to uid/gid","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: honor forceuid/forcegid when mapping SIDs to uid/gid\n\nWhen the administrator mounts with forceuid or forcegid (uid=/gid=\nmount options), they expect all files to appear owned by the specified\nuser/group.  However, several code paths unconditionally called\nsid_to_id() to overwrite cf_uid/cf_gid with server-provided values,\nignoring the administrator's explicit override:\n\n  - smb311_posix_info_to_fattr() (stat via POSIX extensions)\n  - cifs_posix_to_fattr() (readdir via POSIX extensions)\n  - parse_sec_desc() (CIFS ACL ownership mapping)\n\nThis allowed an untrusted server to dictate local file ownership even\nwhen the mount was configured to force specific uid/gid values.\n\nFix all three call sites to check CIFS_MOUNT_OVERR_UID and\nCIFS_MOUNT_OVERR_GID before calling sid_to_id(), following the\nsame pattern already used by cifs_unix_basic_to_fattr() for unix\nextensions.","publishedAt":"2026-09-25T10:21:50.067Z","updatedAt":"2026-10-30T12:37:25.329Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"9409ae58e0759d010b347e7b19ebc90ab5d4b98f","status":"affected","lessThan":"89a3b4704af2208e381c55037ff2d1e2365b83e4","versionType":"git"},{"version":"9409ae58e0759d010b347e7b19ebc90ab5d4b98f","status":"affected","lessThan":"be6eccccec867c22d7c65fab4ea4e91ec3d5b8c6","versionType":"git"},{"version":"9409ae58e0759d010b347e7b19ebc90ab5d4b98f","status":"affected","lessThan":"bc35de451c128d399ad185d6269f8847e97cd1c9","versionType":"git"},{"version":"9409ae58e0759d010b347e7b19ebc90ab5d4b98f","status":"affected","lessThan":"6ac7a29691558bed18e2df1780636b8aa0fd13d5","versionType":"git"},{"version":"9409ae58e0759d010b347e7b19ebc90ab5d4b98f","status":"affected","lessThan":"e1b74f8f8c1d13190b09fe623b729d36b7ac22a8","versionType":"git"},{"version":"9409ae58e0759d010b347e7b19ebc90ab5d4b98f","status":"affected","lessThan":"18a72975e9f35aadecc75b031f693f2d1f49308f","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/smb/client/cifsacl.c","fs/smb/client/inode.c","fs/smb/client/readdir.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"3.0","status":"affected"},{"version":"0","status":"unaffected","lessThan":"3.0","versionType":"semver"},{"version":"6.1.191","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.160","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.114","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.57","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.7","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/smb/client/cifsacl.c","fs/smb/client/inode.c","fs/smb/client/readdir.c"]}],"references":["https://git.kernel.org/stable/c/89a3b4704af2208e381c55037ff2d1e2365b83e4","https://git.kernel.org/stable/c/be6eccccec867c22d7c65fab4ea4e91ec3d5b8c6","https://git.kernel.org/stable/c/bc35de451c128d399ad185d6269f8847e97cd1c9","https://git.kernel.org/stable/c/6ac7a29691558bed18e2df1780636b8aa0fd13d5","https://git.kernel.org/stable/c/e1b74f8f8c1d13190b09fe623b729d36b7ac22a8","https://git.kernel.org/stable/c/18a72975e9f35aadecc75b031f693f2d1f49308f"],"weaknesses":[],"ingestedAt":"2026-10-30T12:56:04.490Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/97xxx/CVE-2026-97561.json","commit":"1f312381e38164a43607eebab851b151dd16861e","baselineCommit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-97561","state":"PUBLISHED","datePublished":"2026-09-25T10:21:50.067Z","dateUpdated":"2026-10-30T12:37:25.329Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-24T16:01:01.155Z"},"containers":{"cna":{"title":"smb: client: honor forceuid/forcegid when mapping SIDs to uid/gid","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: honor forceuid/forcegid when mapping SIDs to uid/gid\n\nWhen the administrator mounts with forceuid or forcegid (uid=/gid=\nmount options), they expect all files to appear owned by the specified\nuser/group.  However, several code paths unconditionally called\nsid_to_id() to overwrite cf_uid/cf_gid with server-provided values,\nignoring the administrator's explicit override:\n\n  - smb311_posix_info_to_fattr() (stat via POSIX extensions)\n  - cifs_posix_to_fattr() (readdir via POSIX extensions)\n  - parse_sec_desc() (CIFS ACL ownership mapping)\n\nThis allowed an untrusted server to dictate local file ownership even\nwhen the mount was configured to force specific uid/gid values.\n\nFix all three call sites to check CIFS_MOUNT_OVERR_UID and\nCIFS_MOUNT_OVERR_GID before calling sid_to_id(), following the\nsame pattern already used by cifs_unix_basic_to_fattr() for unix\nextensions."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"9409ae58e0759d010b347e7b19ebc90ab5d4b98f","status":"affected","lessThan":"89a3b4704af2208e381c55037ff2d1e2365b83e4","versionType":"git"},{"version":"9409ae58e0759d010b347e7b19ebc90ab5d4b98f","status":"affected","lessThan":"be6eccccec867c22d7c65fab4ea4e91ec3d5b8c6","versionType":"git"},{"version":"9409ae58e0759d010b347e7b19ebc90ab5d4b98f","status":"affected","lessThan":"bc35de451c128d399ad185d6269f8847e97cd1c9","versionType":"git"},{"version":"9409ae58e0759d010b347e7b19ebc90ab5d4b98f","status":"affected","lessThan":"6ac7a29691558bed18e2df1780636b8aa0fd13d5","versionType":"git"},{"version":"9409ae58e0759d010b347e7b19ebc90ab5d4b98f","status":"affected","lessThan":"e1b74f8f8c1d13190b09fe623b729d36b7ac22a8","versionType":"git"},{"version":"9409ae58e0759d010b347e7b19ebc90ab5d4b98f","status":"affected","lessThan":"18a72975e9f35aadecc75b031f693f2d1f49308f","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/smb/client/cifsacl.c","fs/smb/client/inode.c","fs/smb/client/readdir.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"3.0","status":"affected"},{"version":"0","status":"unaffected","lessThan":"3.0","versionType":"semver"},{"version":"6.1.191","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.160","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.114","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.57","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.7","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/smb/client/cifsacl.c","fs/smb/client/inode.c","fs/smb/client/readdir.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/89a3b4704af2208e381c55037ff2d1e2365b83e4"},{"url":"https://git.kernel.org/stable/c/be6eccccec867c22d7c65fab4ea4e91ec3d5b8c6"},{"url":"https://git.kernel.org/stable/c/bc35de451c128d399ad185d6269f8847e97cd1c9"},{"url":"https://git.kernel.org/stable/c/6ac7a29691558bed18e2df1780636b8aa0fd13d5"},{"url":"https://git.kernel.org/stable/c/e1b74f8f8c1d13190b09fe623b729d36b7ac22a8"},{"url":"https://git.kernel.org/stable/c/18a72975e9f35aadecc75b031f693f2d1f49308f"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-30T12:37:25.329Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.0","versionEndExcluding":"6.1.191"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.0","versionEndExcluding":"6.6.160"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.0","versionEndExcluding":"6.12.114"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.0","versionEndExcluding":"6.18.57"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.0","versionEndExcluding":"7.2.7"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.0","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}