{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-68100", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-30T09:28:09.368Z", "datePublished": "2026-08-10T11:58:15.233Z", "dateUpdated": "2026-08-10T11:58:15.233Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-10T11:58:15.233Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: validate num_subauth when copying ACE in set_ntacl_dacl\n\nset_ntacl_dacl() copies each ACE from the attacker-controlled stored\nsecurity descriptor verbatim into the response DACL without checking\nsid.num_subauth. The ACE bytes (including an unchecked num_subauth)\noriginate from an authenticated SMB2_SET_INFO(SecInfo=DACL) that is\nstored raw via ksmbd_vfs_set_sd_xattr(); parse_dacl() rejects a bad ACE\nwith `break` rather than an error, so parse_sec_desc() still returns\nsuccess and the malformed SD reaches the xattr intact.\n\nOn a subsequent SMB2_QUERY_INFO(SecInfo=DACL) for an inode carrying a\nPOSIX access ACL, build_sec_desc() -> set_ntacl_dacl() ->\nset_posix_acl_entries_dacl() walks the copied ACEs and reads\n\n ntace->sid.sub_auth[ntace->sid.num_subauth - 1]\n\nwith num_subauth taken straight from the stored SD. Since sub_auth[]\nis fixed at SID_MAX_SUB_AUTHORITIES (15), a crafted num_subauth (e.g.\n255) drives an out-of-bounds heap read of ~1 KB with an offset fully\ncontrolled by an authenticated client.\n\nThe sibling functions already gate this field:\n parse_dacl() -- num_subauth == 0 || > SID_MAX_SUB_AUTHORITIES\n parse_sid() -- num_subauth > SID_MAX_SUB_AUTHORITIES\n smb_copy_sid() -- min_t(u8, num_subauth, SID_MAX_SUB_AUTHORITIES)\nset_ntacl_dacl() is the lone inconsistent path that omits the check.\n\nAdd the same num_subauth validation in set_ntacl_dacl() before copying\nthe ACE, matching the gate already enforced by parse_dacl()."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/smb/server/smbacl.c"], "versions": [{"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "e31fada5143784bc05c7ae44c79eed9b7a2e147e", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "fb3dc8e6da46a1ccad1956cda57de29d9b3033e0", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "b6d3cc6a524416dfdb2b47e4bba2e7e20011d056", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "5acbd3012fd4a7ccfebd91ea6f784120084eb897", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "47f0b34f6bc98ed85bfdc293e8f3e432ec24958d", "status": "affected", "versionType": "git"}, {"version": "0", "lessThan": "6.6.148", "status": "affected", "versionType": "semver"}, {"version": "0", "lessThan": "6.12.101", "status": "affected", "versionType": "semver"}, {"version": "0", "lessThan": "6.18.42", "status": "affected", "versionType": "semver"}, {"version": "0", "lessThan": "7.1.6", "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/smb/server/smbacl.c"], "versions": [{"version": "6.6.148", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.101", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.42", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.1.6", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2-rc2", "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:*:*:*:*:*:*:*:*", "versionEndExcluding": "6.6.148"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "6.12.101"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "6.18.42"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "7.1.6"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "7.2-rc2"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/e31fada5143784bc05c7ae44c79eed9b7a2e147e"}, {"url": "https://git.kernel.org/stable/c/fb3dc8e6da46a1ccad1956cda57de29d9b3033e0"}, {"url": "https://git.kernel.org/stable/c/b6d3cc6a524416dfdb2b47e4bba2e7e20011d056"}, {"url": "https://git.kernel.org/stable/c/5acbd3012fd4a7ccfebd91ea6f784120084eb897"}, {"url": "https://git.kernel.org/stable/c/47f0b34f6bc98ed85bfdc293e8f3e432ec24958d"}], "title": "ksmbd: validate num_subauth when copying ACE in set_ntacl_dacl", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1da177e4c3f41524e886b7f1b8a0c1fc7321cac2,e31fada5143784bc05c7ae44c79eed9b7a2e147e)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1da177e4c3f41524e886b7f1b8a0c1fc7321cac2,fb3dc8e6da46a1ccad1956cda57de29d9b3033e0)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1da177e4c3f41524e886b7f1b8a0c1fc7321cac2,b6d3cc6a524416dfdb2b47e4bba2e7e20011d056)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1da177e4c3f41524e886b7f1b8a0c1fc7321cac2,5acbd3012fd4a7ccfebd91ea6f784120084eb897)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1da177e4c3f41524e886b7f1b8a0c1fc7321cac2,47f0b34f6bc98ed85bfdc293e8f3e432ec24958d)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,6.6.148)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,6.12.101)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,6.18.42)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,7.1.6)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.6.148,6.7.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.101,6.13.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.42,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.1.6,7.2.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.2-rc2,*)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-08-10T13:30:05.188954+00:00", "updated": "2026-08-10T14:15:03.639149+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"], "weaknesses": ["CWE-125"]}