{ "schemaVersion": 1, "attribution": [ { "source": "CISA Known Exploited Vulnerabilities", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "licence": "US government work" }, { "source": "GitHub Advisory Database", "url": "https://github.com/advisories", "licence": "CC BY 4.0" }, { "source": "Have I Been Pwned", "url": "https://haveibeenpwned.com/", "licence": "CC BY 4.0" }, { "source": "CVE Program (CVE records)", "url": "https://www.cve.org/Legal/TermsOfUse", "licence": "CVE Terms of Use", "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.", "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss/", "licence": "free to use; FIRST requests attribution" } ], "record": { "id": "CVE-2026-53390", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-53390", "idYear": 2026, "status": "PUBLISHED", "publishedAt": "2026-07-19T12:01:54.951Z", "updatedAt": "2026-08-17T04:50:41.549Z", "importedAt": "2026-10-24T01:58:20.586Z", "snapshot": { "id": "cve_2026-10-24_midnight_baseline", "at": "2026-10-24T00:00:00.000Z", "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z" }, "facts": { "title": "ksmbd: fix out-of-bounds read in smb_check_perm_dacl()", "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix out-of-bounds read in smb_check_perm_dacl()\n\nThe permission-check ACE walk in smb_check_perm_dacl() validates the ACE\nheader size and caps sid.num_subauth at SID_MAX_SUB_AUTHORITIES, but it\nnever checks that ace->size is actually large enough to contain\nnum_subauth sub-authorities before compare_sids() dereferences them.\n\nCIFS_SID_BASE_SIZE covers the SID header up to but excluding the\nsub_auth[] array, and offsetof(struct smb_ace, sid) is the ACE header,\nso the existing guards only guarantee the 8-byte SID base, i.e. zero\nsub-authorities. compare_sids() then reads ace->sid.sub_auth[i] for\ni < min(local_sid->num_subauth, ace->sid.num_subauth). The local\ncomparison SIDs (sid_everyone, sid_unix_NFS_mode, and the id_to_sid()\nresult) always have at least one sub-authority, and an attacker controls\nthe ACE revision and authority bytes (which lie within the in-bounds SID\nbase), so they can match one of those SIDs and force the sub_auth read.\n\nA crafted ACE with size == 16 and num_subauth >= 1 placed at the tail of\nthe security descriptor therefore causes a heap out-of-bounds read of up\nto SID_MAX_SUB_AUTHORITIES * sizeof(__le32) bytes past the pntsd\nallocation. The security descriptor is loaded by ksmbd_vfs_get_sd_xattr()\ninto a buffer sized exactly to the on-disk data (kzalloc(sd_size) in\nndr_decode_v4_ntacl()), so the read lands past the allocation. The\nmalformed descriptor can be stored verbatim via SMB2_SET_INFO (the DACL\nis not normalised before being written to the security.NTACL xattr) and\nthe read fires on a subsequent SMB2_CREATE access check, making this\nreachable by an authenticated client on a share that uses ACL xattrs.\n\nAdd the missing num_subauth-versus-ace_size check, mirroring the\nidentical guards already present in the sibling parsers parse_dacl() and\nsmb_inherit_dacl().", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "282cbbb476b9f35793452bc461934af4c7eca169", "status": "affected", "versionType": "git", "lessThan": "c7488c85fd822959e9b5c22fbd9e7c8a21caf5e0" }, { "version": "f20adc4ef7428bc485ee83fd1a592252fb87718b", "status": "affected", "versionType": "git", "lessThan": "988c93d3bba066d8669143e6ec30bb2be9608d53" }, { "version": "325d4ac11f526cb8964cff14548ccf02d8c756d8", "status": "affected", "versionType": "git", "lessThan": "36599894fa8536fefdf1e296c0af71b8b7226859" }, { "version": "95e5aa3c3261da8c95b27d7aecf8ee39b9f86a4c", "status": "affected", "versionType": "git", "lessThan": "d5c81a095c86fe507c032d08f3a8cfc518444927" }, { "version": "90089584b2e25c4510b7b987387b4405f0673ece", "status": "affected", "versionType": "git", "lessThan": "7627ff8c4f9919f14de562b0160ab4ec9d80b1f7" }, { "version": "d07b26f39246a82399661936dd0c853983cfade7", "status": "affected", "versionType": "git", "lessThan": "e36e35660adb9b8ef1435ac359151dda5f094c55" }, { "version": "d07b26f39246a82399661936dd0c853983cfade7", "status": "affected", "versionType": "git", "lessThan": "1ef06004ed4bd6d3ed8c840d9d1a376b66d4935b" }, { "version": "151b1799861fde38087c08f613abc2843ef597b0", "status": "affected", "versionType": "git" }, { "version": "5.15.210", "status": "affected", "versionType": "semver", "lessThan": "5.15.212" }, { "version": "6.1.176", "status": "affected", "versionType": "semver", "lessThan": "6.1.177" }, { "version": "6.6.140", "status": "affected", "versionType": "semver", "lessThan": "6.6.144" }, { "version": "6.12.84", "status": "affected", "versionType": "semver", "lessThan": "6.12.95" }, { "version": "6.18.25", "status": "affected", "versionType": "semver", "lessThan": "6.18.38" }, { "version": "7.0.2", "status": "affected", "versionType": "semver", "lessThan": "7.1" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "7.1", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "7.1" }, { "version": "5.15.212", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.15.*" }, { "version": "6.1.177", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.1.*" }, { "version": "6.6.144", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.6.*" }, { "version": "6.12.95", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.12.*" }, { "version": "6.18.38", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.18.*" }, { "version": "7.1.3", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "7.1.*" }, { "version": "7.2", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }