{"id":"CVE-2025-38092","state":"PUBLISHED","title":"ksmbd: use list_first_entry_or_null for opinfo_get_list()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: use list_first_entry_or_null for opinfo_get_list()\n\nThe list_first_entry() macro never returns NULL.  If the list is\nempty then it returns an invalid pointer.  Use list_first_entry_or_null()\nto check if the list is empty.","publishedAt":"2025-07-02T14:43:30.776Z","updatedAt":"2026-08-05T11:59:27.724Z","severity":{"score":8.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"296cb5457cc6f4a754c4ae29855f8a253d52bcc6","status":"affected","lessThan":"c78abb646ff823e7d22faad4cc0703d4484da9e8","versionType":"git"},{"version":"d54ab1520d43e95f9b2e22d7a05fc9614192e5a5","status":"affected","lessThan":"334da674b25fdb7a1a4d4b89dcd7795144fc7e11","versionType":"git"},{"version":"d73686367ad68534257cd88a36ca3c52cb8b81d8","status":"affected","lessThan":"cb7e06e9736d73007dc8dab7b353733bb37df86b","versionType":"git"},{"version":"18b4fac5ef17f77fed9417d22210ceafd6525fc7","status":"affected","lessThan":"10379171f346e6f61d30d9949500a8de4336444a","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/smb/server/oplock.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"6.6.88","status":"affected","lessThan":"6.6.93","versionType":"semver"},{"version":"6.12.25","status":"affected","lessThan":"6.12.32","versionType":"semver"},{"version":"6.14.4","status":"affected","lessThan":"6.14.10","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/smb/server/oplock.c"]}],"references":["https://git.kernel.org/stable/c/c78abb646ff823e7d22faad4cc0703d4484da9e8","https://git.kernel.org/stable/c/334da674b25fdb7a1a4d4b89dcd7795144fc7e11","https://git.kernel.org/stable/c/cb7e06e9736d73007dc8dab7b353733bb37df86b","https://git.kernel.org/stable/c/10379171f346e6f61d30d9949500a8de4336444a"],"weaknesses":[],"ingestedAt":"2026-10-29T20:09:09.358Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2025/38xxx/CVE-2025-38092.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-38092","state":"PUBLISHED","datePublished":"2025-07-02T14:43:30.776Z","dateUpdated":"2026-08-05T11:59:27.724Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2025-04-16T04:51:23.983Z"},"containers":{"cna":{"title":"ksmbd: use list_first_entry_or_null for opinfo_get_list()","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: use list_first_entry_or_null for opinfo_get_list()\n\nThe list_first_entry() macro never returns NULL.  If the list is\nempty then it returns an invalid pointer.  Use list_first_entry_or_null()\nto check if the list is empty."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"296cb5457cc6f4a754c4ae29855f8a253d52bcc6","status":"affected","lessThan":"c78abb646ff823e7d22faad4cc0703d4484da9e8","versionType":"git"},{"version":"d54ab1520d43e95f9b2e22d7a05fc9614192e5a5","status":"affected","lessThan":"334da674b25fdb7a1a4d4b89dcd7795144fc7e11","versionType":"git"},{"version":"d73686367ad68534257cd88a36ca3c52cb8b81d8","status":"affected","lessThan":"cb7e06e9736d73007dc8dab7b353733bb37df86b","versionType":"git"},{"version":"18b4fac5ef17f77fed9417d22210ceafd6525fc7","status":"affected","lessThan":"10379171f346e6f61d30d9949500a8de4336444a","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/smb/server/oplock.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"6.6.88","status":"affected","lessThan":"6.6.93","versionType":"semver"},{"version":"6.12.25","status":"affected","lessThan":"6.12.32","versionType":"semver"},{"version":"6.14.4","status":"affected","lessThan":"6.14.10","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/smb/server/oplock.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/c78abb646ff823e7d22faad4cc0703d4484da9e8"},{"url":"https://git.kernel.org/stable/c/334da674b25fdb7a1a4d4b89dcd7795144fc7e11"},{"url":"https://git.kernel.org/stable/c/cb7e06e9736d73007dc8dab7b353733bb37df86b"},{"url":"https://git.kernel.org/stable/c/10379171f346e6f61d30d9949500a8de4336444a"}],"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; the vulnerable path is driven entirely by remote SMB2 CREATE, LOCK and CLOSE requests arriving on TCP/445 from a remote client. No local access is required.\nAC:L - The attacker controls both sides of the race by issuing concurrent SMB2 CREATE/LOCK and CLOSE requests on multiple connections against the same file, and the window is actively widened because down_read() in opinfo_get_list() blocks behind the racing opinfo_del() down_write() that empties the list.\nPR:L - Reaching smb_grant_oplock()/smb_break_all_oplock() requires an established SMB2 session, a tree connect and open file handles, so a valid (even low-privilege or guest-mapped) SMB account is needed; this is not a pre-authentication code path.\nUI:N - The attacker drives every step from its own SMB connections — opening handles with oplocks/leases and closing them concurrently. No action by any other user or administrator is needed.\nS:U - The type confusion corrupts kernel heap memory belonging to the ksmbd subsystem within the same kernel security authority; no VM, IOMMU or sandbox boundary is crossed.\nC:H - The fake oplock_info causes reads through attacker-timed wild pointers — opinfo->conn resolves to an rwsem waiter on another task's kernel stack and o_lease to an arbitrary kernel pointer — and such heap type confusion is leverageable into arbitrary kernel memory disclosure.\nI:H - atomic_inc_not_zero() performs a real RMW write onto the upper half of ksmbd_inode->m_hash.pprev, corrupting a kernel pointer that hlist_del_init() later writes through, and follow-on oplock_break()/opinfo_put() paths add out-of-bounds wait-queue list writes and kfree() of interior pointers — classic type confusion promotable to a write primitive.\nA:H - Dereferencing and atomically modifying a bogus pointer derived from the list head, plus spinlock/wait-queue operations past the end of the kmalloc'd ksmbd_inode, reliably produce slab corruption, oops or panic, taking down the file server host."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-05T11:59:27.724Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.6.88","versionEndExcluding":"6.6.93"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12.25","versionEndExcluding":"6.12.32"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.14.4","versionEndExcluding":"6.14.10"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}