{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2025-37926", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-04-16T04:51:23.969Z", "datePublished": "2025-05-20T15:21:53.359Z", "dateUpdated": "2026-08-05T11:58:26.156Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T11:58:26.156Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix use-after-free in ksmbd_session_rpc_open\n\nA UAF issue can occur due to a race condition between\nksmbd_session_rpc_open() and __session_rpc_close().\nAdd rpc_lock to the session to protect it." } ], "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/445; the entire attack consists of SMB2 CREATE and CLOSE PDUs sent over the network to the IPC$ share. No local access is needed at any point.\nAC:L - The attacker drives both sides of the race by pipelining concurrent SMB2 requests on one connection (ksmbd's workqueue has no per-connection serialization), and the race window spans a blocking userspace IPC round-trip of up to 2 seconds, while the target handle ID is a predictable small `ida_alloc()` value.\nPR:L - Reaching create_smb2_pipe() requires a completed SMB2 SESSION_SETUP and a TREE_CONNECT to IPC$, i.e. any valid low-privileged SMB account (or a guest account where mapping is enabled). This matches the scoring of the sibling ksmbd session UAFs CVE-2025-22040/CVE-2025-22041.\nUI:N - The attacker generates every request in the sequence; no action by a legitimate user or administrator is required to trigger the race.\nS:U - The corruption is confined to the kernel's own heap and the ksmbd server's data structures, all within the same security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - The success path returns `entry->id` read from freed slab memory and sends it back to the attacker as the CREATE response VolatileFileId, directly leaking reclaimed kernel heap contents, and the UAF/double-free of a small generic-cache object gives a spray-controlled read primitive.\nI:H - The error path double-frees the entry and calls ksmbd_rpc_id_free() on a stale IDA id now owned by a different live RPC handle, yielding freelist corruption and cross-handle aliasing that are classic stepping stones to arbitrary write and control-flow hijack in kernel context.\nA:H - Use-after-free and double-free of a kmalloc object reliably produce slab corruption, oops, or panic, and the attacker can repeat the race indefinitely over new sessions to crash the server." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/smb/server/mgmt/user_session.c", "fs/smb/server/mgmt/user_session.h" ], "versions": [ { "version": "0626e6641f6b467447c81dd7678a69c66f7746cf", "lessThan": "a4348710a7267705b75692dc1a000920481d1d92", "status": "affected", "versionType": "git" }, { "version": "0626e6641f6b467447c81dd7678a69c66f7746cf", "lessThan": "1067361a1cc6ad9cdf7acfc47f90012b72ad1502", "status": "affected", "versionType": "git" }, { "version": "0626e6641f6b467447c81dd7678a69c66f7746cf", "lessThan": "8fb3b6c85b7e3127161623586b62abcc366caa20", "status": "affected", "versionType": "git" }, { "version": "0626e6641f6b467447c81dd7678a69c66f7746cf", "lessThan": "6323fec65fe54b365961fed260dd579191e46121", "status": "affected", "versionType": "git" }, { "version": "0626e6641f6b467447c81dd7678a69c66f7746cf", "lessThan": "a1f46c99d9ea411f9bf30025b912d881d36fc709", "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/mgmt/user_session.c", "fs/smb/server/mgmt/user_session.h" ], "versions": [ { "version": "5.15", "status": "affected" }, { "version": "0", "lessThan": "5.15", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.162", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.122", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.28", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.14.6", "lessThanOrEqual": "6.14.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.15", "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": "6.1.162" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.6.122" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.12.28" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.14.6" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.15" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/a4348710a7267705b75692dc1a000920481d1d92" }, { "url": "https://git.kernel.org/stable/c/1067361a1cc6ad9cdf7acfc47f90012b72ad1502" }, { "url": "https://git.kernel.org/stable/c/8fb3b6c85b7e3127161623586b62abcc366caa20" }, { "url": "https://git.kernel.org/stable/c/6323fec65fe54b365961fed260dd579191e46121" }, { "url": "https://git.kernel.org/stable/c/a1f46c99d9ea411f9bf30025b912d881d36fc709" } ], "title": "ksmbd: fix use-after-free in ksmbd_session_rpc_open", "x_generator": { "engine": "bippy-1.2.0" } } } }