{"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"}}]}}