{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-31433", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-03-09T15:48:24.089Z", "datePublished": "2026-04-22T08:15:11.719Z", "dateUpdated": "2026-08-05T12:22:27.773Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:22:27.773Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix potencial OOB in get_file_all_info() for compound requests\n\nWhen a compound request consists of QUERY_DIRECTORY + QUERY_INFO\n(FILE_ALL_INFORMATION) and the first command consumes nearly the entire\nmax_trans_size, get_file_all_info() would blindly call smbConvertToUTF16()\nwith PATH_MAX, causing out-of-bounds write beyond the response buffer.\nIn get_file_all_info(), there was a missing validation check for\nthe client-provided OutputBufferLength before copying the filename into\nFileName field of the smb2_file_all_info structure.\nIf the filename length exceeds the available buffer space, it could lead to\npotential buffer overflows or memory corruption during smbConvertToUTF16\nconversion. This calculating the actual free buffer size using\nsmb2_calc_max_out_buf_len() and returning -EINVAL if the buffer is\ninsufficient and updating smbConvertToUTF16 to use the actual filename\nlength (clamped by PATH_MAX) to ensure a safe copy operation." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 8.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:N - ksmbd is the in-kernel SMB server listening on TCP port 445, directly reachable over the network by any SMB client.\nAC:L - The attacker can reliably construct a compound request (QUERY_DIRECTORY + QUERY_INFO) where the first command consumes most of the buffer, then trigger the OOB write in the second command with no race conditions or special prerequisites.\nPR:L - The vulnerability requires an authenticated SMB session and tree connection; smb2_check_user_session() and smb2_get_ksmbd_tcon() are enforced before QUERY_INFO is processed, so the attacker needs valid SMB credentials.\nUI:N - No user interaction is required; the attacker sends the malicious compound SMB request directly over the network.\nS:U - The vulnerability stays within the kernel security scope; there is no crossing of a security boundary like VM escape or sandbox escape.\nC:H - The out-of-bounds heap write of up to ~8KB of attacker-influenced data into kernel heap can be leveraged to corrupt adjacent objects and create read primitives for arbitrary kernel memory disclosure.\nI:H - The OOB heap write corrupts adjacent kernel heap objects with partially attacker-controlled data (UTF-16 filename), which can be exploited via heap shaping for arbitrary write primitives and code execution.\nA:H - The out-of-bounds write corrupts kernel heap memory, which will reliably cause kernel crashes or panics." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/smb/server/smb2pdu.c" ], "versions": [ { "version": "f2283680a80571ca82d710bc6ecd8f8beac67d63", "lessThan": "3a852f9d1c981fb14f6bf4e24999e0ea8088a7d7", "status": "affected", "versionType": "git" }, { "version": "9f297df20d93411c0b4ddad7f88ba04a7cd36e77", "lessThan": "4cca3eff2099b18672934a39cee70aed835d652c", "status": "affected", "versionType": "git" }, { "version": "e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d", "lessThan": "358cdaa1f7fbf2712cb4c5f6b59cb9a5c673c5fe", "status": "affected", "versionType": "git" }, { "version": "e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d", "lessThan": "7aec5a769d2356cbf344d85bcfd36de592ac96a5", "status": "affected", "versionType": "git" }, { "version": "e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d", "lessThan": "b0cd9725fe2bcc9f37d096b132318a9060373f5d", "status": "affected", "versionType": "git" }, { "version": "e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d", "lessThan": "9d7032851d6f5adbe2739601ca456c0ad3b422f0", "status": "affected", "versionType": "git" }, { "version": "e2b76ab8b5c9327ab2dae6da05d0752eb2f4771d", "lessThan": "beef2634f81f1c086208191f7228bce1d366493d", "status": "affected", "versionType": "git" }, { "version": "5.15.145", "lessThan": "5.15.203", "status": "affected", "versionType": "semver" }, { "version": "6.1.71", "lessThan": "6.1.168", "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/smb2pdu.c" ], "versions": [ { "version": "6.6", "status": "affected" }, { "version": "0", "lessThan": "6.6", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.203", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.168", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.131", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.80", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.21", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.19.11", "lessThanOrEqual": "6.19.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.0", "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": "5.15.145", "versionEndExcluding": "5.15.203" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1.71", "versionEndExcluding": "6.1.168" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6", "versionEndExcluding": "6.6.131" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6", "versionEndExcluding": "6.12.80" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6", "versionEndExcluding": "6.18.21" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6", "versionEndExcluding": "6.19.11" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6", "versionEndExcluding": "7.0" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/3a852f9d1c981fb14f6bf4e24999e0ea8088a7d7" }, { "url": "https://git.kernel.org/stable/c/4cca3eff2099b18672934a39cee70aed835d652c" }, { "url": "https://git.kernel.org/stable/c/358cdaa1f7fbf2712cb4c5f6b59cb9a5c673c5fe" }, { "url": "https://git.kernel.org/stable/c/7aec5a769d2356cbf344d85bcfd36de592ac96a5" }, { "url": "https://git.kernel.org/stable/c/b0cd9725fe2bcc9f37d096b132318a9060373f5d" }, { "url": "https://git.kernel.org/stable/c/9d7032851d6f5adbe2739601ca456c0ad3b422f0" }, { "url": "https://git.kernel.org/stable/c/beef2634f81f1c086208191f7228bce1d366493d" } ], "title": "ksmbd: fix potencial OOB in get_file_all_info() for compound requests", "x_generator": { "engine": "bippy-1.2.0" } } } }