{"api_version":"1","generated_at":"2026-08-12T05:06:31+00:00","cve":"CVE-2026-68099","urls":{"html":"https://cve.report/CVE-2026-68099","api":"https://cve.report/api/cve/CVE-2026-68099.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-68099","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-68099"},"summary":{"title":"ksmbd: restore DACL size on check_add_overflow() to avoid malformed ACL","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: restore DACL size on check_add_overflow() to avoid malformed ACL\n\ncheck_add_overflow() unconditionally writes the truncated sum into *d\neven on overflow, per its contract in include/linux/overflow.h.\nThe four check_add_overflow() guards in set_posix_acl_entries_dacl()\nand set_ntacl_dacl() break out of the ACE-building loops on overflow,\nbut the truncated *size is then consumed downstream at the end of\nset_ntacl_dacl():\n\n    pndacl->size = cpu_to_le16(le16_to_cpu(pndacl->size) + size);\n\nThis produces an on-wire NT ACL whose pndacl->size under-reports the\nbytes actually written by the preceding fill_ace_for_sid()/memcpy()\ncalls, yielding a malformed ACL that can trigger out-of-bounds reads\nwhen re-parsed by clients or ksmbd itself.\n\nRestore *size to its pre-addition value on each overflow branch (via\n`*size -= ace_sz` / `size -= nt_ace_size`) so that after the break,\n*size once again holds the cumulative size of the successfully-written\nACEs. The committed ACL is then truncated-but-self-consistent rather\nthan malformed.\n\nThe ksmbd DACL builders are the only check_add_overflow() sites found\nwhere an overflow path breaks out of a loop and the destination value\nis consumed afterward. The other nearby break-style cases either\nreturn -EINVAL on overflow (transport_ipc.c) or break without\nconsuming the overflowed destination value afterward (buildid.c).","state":"PUBLISHED","assigner":"Linux","published_at":"2026-08-10 13:19:54","updated_at":"2026-08-10 13:19:54"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/0bf38372821b1526f31538a7d9811844c55c7f38","name":"https://git.kernel.org/stable/c/0bf38372821b1526f31538a7d9811844c55c7f38","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/bc90144ce8bb7fcf05ad9417c7adb4e9509d9e13","name":"https://git.kernel.org/stable/c/bc90144ce8bb7fcf05ad9417c7adb4e9509d9e13","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/847ecd4eb3c117c3d2f13f1e7ab506543aad8183","name":"https://git.kernel.org/stable/c/847ecd4eb3c117c3d2f13f1e7ab506543aad8183","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/bbf0a8e931204ecdab494a88d43b0a24a04285c5","name":"https://git.kernel.org/stable/c/bbf0a8e931204ecdab494a88d43b0a24a04285c5","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/f4fcd0c1a243d449307b887fafee23921e9db5ab","name":"https://git.kernel.org/stable/c/f4fcd0c1a243d449307b887fafee23921e9db5ab","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-68099","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-68099","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 8d5729350b236896f51379588d9a690b7fafb8db f4fcd0c1a243d449307b887fafee23921e9db5ab git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e1955a94b6f17f4b058afa955a6f187eb3ed7615 0bf38372821b1526f31538a7d9811844c55c7f38 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5e7b8f3c539d69b2ed5f2408e2f75e68ce7eef43 847ecd4eb3c117c3d2f13f1e7ab506543aad8183 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 299f962c0b02d048fb45d248b4da493d03f3175d bc90144ce8bb7fcf05ad9417c7adb4e9509d9e13 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 299f962c0b02d048fb45d248b4da493d03f3175d bbf0a8e931204ecdab494a88d43b0a24a04285c5 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 41e53a773db6342ac9a689ee5ba635c31744c9f0 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected ef7902be3f215b6bf7babe4dc9dd9a7d57dad7a7 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.6.136 6.6.148 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.12.84 6.12.101 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.18.25 6.18.42 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.1.175 6.2 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7.0.2 7.1 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7.1","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.148 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.101 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.42 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1.6 7.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2-rc5 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["fs/smb/server/smbacl.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"f4fcd0c1a243d449307b887fafee23921e9db5ab","status":"affected","version":"8d5729350b236896f51379588d9a690b7fafb8db","versionType":"git"},{"lessThan":"0bf38372821b1526f31538a7d9811844c55c7f38","status":"affected","version":"e1955a94b6f17f4b058afa955a6f187eb3ed7615","versionType":"git"},{"lessThan":"847ecd4eb3c117c3d2f13f1e7ab506543aad8183","status":"affected","version":"5e7b8f3c539d69b2ed5f2408e2f75e68ce7eef43","versionType":"git"},{"lessThan":"bc90144ce8bb7fcf05ad9417c7adb4e9509d9e13","status":"affected","version":"299f962c0b02d048fb45d248b4da493d03f3175d","versionType":"git"},{"lessThan":"bbf0a8e931204ecdab494a88d43b0a24a04285c5","status":"affected","version":"299f962c0b02d048fb45d248b4da493d03f3175d","versionType":"git"},{"status":"affected","version":"41e53a773db6342ac9a689ee5ba635c31744c9f0","versionType":"git"},{"status":"affected","version":"ef7902be3f215b6bf7babe4dc9dd9a7d57dad7a7","versionType":"git"},{"lessThan":"6.6.148","status":"affected","version":"6.6.136","versionType":"semver"},{"lessThan":"6.12.101","status":"affected","version":"6.12.84","versionType":"semver"},{"lessThan":"6.18.42","status":"affected","version":"6.18.25","versionType":"semver"},{"lessThan":"6.2","status":"affected","version":"6.1.175","versionType":"semver"},{"lessThan":"7.1","status":"affected","version":"7.0.2","versionType":"semver"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["fs/smb/server/smbacl.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"7.1"},{"lessThan":"7.1","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.148","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.101","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.42","versionType":"semver"},{"lessThanOrEqual":"7.1.*","status":"unaffected","version":"7.1.6","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.2-rc5","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.148","versionStartIncluding":"6.6.136","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.101","versionStartIncluding":"6.12.84","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.42","versionStartIncluding":"6.18.25","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1.6","versionStartIncluding":"7.1","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2-rc5","versionStartIncluding":"7.1","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1.175","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"7.0.2","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: restore DACL size on check_add_overflow() to avoid malformed ACL\n\ncheck_add_overflow() unconditionally writes the truncated sum into *d\neven on overflow, per its contract in include/linux/overflow.h.\nThe four check_add_overflow() guards in set_posix_acl_entries_dacl()\nand set_ntacl_dacl() break out of the ACE-building loops on overflow,\nbut the truncated *size is then consumed downstream at the end of\nset_ntacl_dacl():\n\n    pndacl->size = cpu_to_le16(le16_to_cpu(pndacl->size) + size);\n\nThis produces an on-wire NT ACL whose pndacl->size under-reports the\nbytes actually written by the preceding fill_ace_for_sid()/memcpy()\ncalls, yielding a malformed ACL that can trigger out-of-bounds reads\nwhen re-parsed by clients or ksmbd itself.\n\nRestore *size to its pre-addition value on each overflow branch (via\n`*size -= ace_sz` / `size -= nt_ace_size`) so that after the break,\n*size once again holds the cumulative size of the successfully-written\nACEs. The committed ACL is then truncated-but-self-consistent rather\nthan malformed.\n\nThe ksmbd DACL builders are the only check_add_overflow() sites found\nwhere an overflow path breaks out of a loop and the destination value\nis consumed afterward. The other nearby break-style cases either\nreturn -EINVAL on overflow (transport_ipc.c) or break without\nconsuming the overflowed destination value afterward (buildid.c)."}],"providerMetadata":{"dateUpdated":"2026-08-10T11:58:13.940Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/f4fcd0c1a243d449307b887fafee23921e9db5ab"},{"url":"https://git.kernel.org/stable/c/0bf38372821b1526f31538a7d9811844c55c7f38"},{"url":"https://git.kernel.org/stable/c/847ecd4eb3c117c3d2f13f1e7ab506543aad8183"},{"url":"https://git.kernel.org/stable/c/bc90144ce8bb7fcf05ad9417c7adb4e9509d9e13"},{"url":"https://git.kernel.org/stable/c/bbf0a8e931204ecdab494a88d43b0a24a04285c5"}],"title":"ksmbd: restore DACL size on check_add_overflow() to avoid malformed ACL","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-68099","datePublished":"2026-08-10T11:58:13.940Z","dateReserved":"2026-07-30T09:28:09.368Z","dateUpdated":"2026-08-10T11:58:13.940Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-08-10 13:19:54","lastModifiedDate":"2026-08-10 13:19:54","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"68099","Ordinal":"1","Title":"ksmbd: restore DACL size on check_add_overflow() to avoid malfor","CVE":"CVE-2026-68099","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"68099","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: restore DACL size on check_add_overflow() to avoid malformed ACL\n\ncheck_add_overflow() unconditionally writes the truncated sum into *d\neven on overflow, per its contract in include/linux/overflow.h.\nThe four check_add_overflow() guards in set_posix_acl_entries_dacl()\nand set_ntacl_dacl() break out of the ACE-building loops on overflow,\nbut the truncated *size is then consumed downstream at the end of\nset_ntacl_dacl():\n\n    pndacl->size = cpu_to_le16(le16_to_cpu(pndacl->size) + size);\n\nThis produces an on-wire NT ACL whose pndacl->size under-reports the\nbytes actually written by the preceding fill_ace_for_sid()/memcpy()\ncalls, yielding a malformed ACL that can trigger out-of-bounds reads\nwhen re-parsed by clients or ksmbd itself.\n\nRestore *size to its pre-addition value on each overflow branch (via\n`*size -= ace_sz` / `size -= nt_ace_size`) so that after the break,\n*size once again holds the cumulative size of the successfully-written\nACEs. The committed ACL is then truncated-but-self-consistent rather\nthan malformed.\n\nThe ksmbd DACL builders are the only check_add_overflow() sites found\nwhere an overflow path breaks out of a loop and the destination value\nis consumed afterward. The other nearby break-style cases either\nreturn -EINVAL on overflow (transport_ipc.c) or break without\nconsuming the overflowed destination value afterward (buildid.c).","Type":"Description","Title":"ksmbd: restore DACL size on check_add_overflow() to avoid malfor"}]}}}