{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2025-38191", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-04-16T04:51:23.993Z", "datePublished": "2025-07-04T13:37:15.736Z", "dateUpdated": "2026-08-05T12:00:16.004Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:00:16.004Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix null pointer dereference in destroy_previous_session\n\nIf client set ->PreviousSessionId on kerberos session setup stage,\nNULL pointer dereference error will happen. Since sess->user is not\nset yet, It can pass the user argument as NULL to destroy_previous_session.\nsess->user will be set in ksmbd_krb5_authenticate(). So this patch move\ncalling destroy_previous_session() after ksmbd_krb5_authenticate()." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "baseScore": 7.5, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:N - ksmbd is the in-kernel SMB3 server processing SMB2 SESSION_SETUP requests over TCP port 445; the malformed PreviousSessionId arrives from a remote network peer.\nAC:L - The attacker deterministically controls both the prior session and the second connection's PreviousSessionId with no race or uncontrolled memory-layout dependency; the NULL deref triggers reliably.\nPR:N - The crash occurs during the Kerberos handshake before the second connection's credentials are verified, and the required prior session can be created pre-authentication in a reasonable deployment (guest access), so no privileges are needed.\nUI:N - Exploitation requires only attacker-sent SMB2 packets; no action by any local user or victim is needed.\nS:U - The NULL dereference crashes the kernel within its own security scope; no boundary (VM, IOMMU, sandbox) is crossed.\nC:N - A NULL pointer dereference is a pure crash that discloses no memory contents or kernel data.\nI:N - The bug provides no write primitive or data modification; it only faults on a NULL read of user->name.\nA:H - The NULL dereference causes a kernel oops/panic, taking down the SMB server and the host, and can be triggered repeatedly." } ] } ], "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": "0626e6641f6b467447c81dd7678a69c66f7746cf", "lessThan": "281afc52e2961cd5dd8326ebc9c5bc40904c0468", "status": "affected", "versionType": "git" }, { "version": "0626e6641f6b467447c81dd7678a69c66f7746cf", "lessThan": "0902625a24eea7fdc187faa5d97df244d159dd6e", "status": "affected", "versionType": "git" }, { "version": "0626e6641f6b467447c81dd7678a69c66f7746cf", "lessThan": "1193486dffb7432a09f57f5d09049b4d4123538b", "status": "affected", "versionType": "git" }, { "version": "0626e6641f6b467447c81dd7678a69c66f7746cf", "lessThan": "076f1adefb9837977af7ed233883842ddc446644", "status": "affected", "versionType": "git" }, { "version": "0626e6641f6b467447c81dd7678a69c66f7746cf", "lessThan": "7ac5b66acafcc9292fb935d7e03790f2b8b2dc0e", "status": "affected", "versionType": "git" } ] }, { "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": "5.15", "status": "affected" }, { "version": "0", "lessThan": "5.15", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.142", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.95", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.35", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.15.4", "lessThanOrEqual": "6.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.16", "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", "versionEndExcluding": "6.1.142" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.6.95" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.12.35" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.15.4" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.16" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/281afc52e2961cd5dd8326ebc9c5bc40904c0468" }, { "url": "https://git.kernel.org/stable/c/0902625a24eea7fdc187faa5d97df244d159dd6e" }, { "url": "https://git.kernel.org/stable/c/1193486dffb7432a09f57f5d09049b4d4123538b" }, { "url": "https://git.kernel.org/stable/c/076f1adefb9837977af7ed233883842ddc446644" }, { "url": "https://git.kernel.org/stable/c/7ac5b66acafcc9292fb935d7e03790f2b8b2dc0e" }, { "url": "https://www.zerodayinitiative.com/advisories/ZDI-25-610/" } ], "title": "ksmbd: fix null pointer dereference in destroy_previous_session", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "title": "CVE Program Container", "references": [ { "url": "https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html" } ], "providerMetadata": { "orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2025-11-03T17:35:15.212Z" } } ] } }