{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2023-53006", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-03-27T16:40:15.745Z", "datePublished": "2025-03-27T16:43:37.225Z", "dateUpdated": "2026-08-05T09:12:20.807Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T09:12:20.807Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncifs: Fix oops due to uncleared server->smbd_conn in reconnect\n\nIn smbd_destroy(), clear the server->smbd_conn pointer after freeing the\nsmbd_connection struct that it points to so that reconnection doesn't get\nconfused." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 9.8, "baseSeverity": "CRITICAL" }, "scenarios": [ { "lang": "en", "value": "AV:N - The UAF is in the CIFS client's SMB Direct reconnect path (`cifs_abort_connection` → `smbd_destroy` → `smbd_reconnect`), driven by a remote peer dropping the RDMA/iWARP connection; iWARP/RoCEv2 are IP-reachable so a malicious or compromised SMB Direct server is a network attacker.\nAC:L - After any disconnect, `__cifs_reconnect` deterministically frees `smbd_conn` then immediately dereferences the dangling pointer in `smbd_reconnect`; the remote peer forces disconnects at will and can retry unboundedly every reconnect cycle.\nPR:N - The attacker is the remote SMB Direct server (or on-path peer) and needs no account or privileges on the victim; the vulnerable abort/reconnect runs in the cifsd kernel thread on the transport before SMB re-authentication.\nUI:N - Against an already-mounted `rdma` CIFS share (typical fstab/autofs enterprise setup), cifsd automatically reconnects on peer disconnect with no victim action at exploit time.\nS:U - The use-after-free corrupts host kernel heap (`smbd_connection` in kmalloc-4k) within the same OS security authority and does not cross a VM, IOMMU, or sandbox boundary.\nC:H - This is a use-after-free of the heap-allocated `smbd_connection`; reclaim/grooming of the freed object lets the reconnect path read attacker-influenced fields (e.g. `transport_status`), yielding a kernel disclosure primitive per UAF guidance.\nI:H - If the reclaimed object presents `transport_status == SMBD_CONNECTED`, `smbd_destroy` runs RDMA teardown (disconnect, QP drain, frees) on attacker-controlled structure fields, giving a classic heap UAF write/control-flow hijack primitive.\nA:H - The dangling `server->smbd_conn` dereference is a confirmed KASAN use-after-free/oops in `smbd_reconnect` during reconnect and is repeatedly triggerable by peer disconnects." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/cifs/smbdirect.c" ], "versions": [ { "version": "8ef130f9ec27973f7b49e20c5a3b9134ca33026c", "lessThan": "a9640c0b268405f2540e8203a545e930ea88bb7d", "status": "affected", "versionType": "git" }, { "version": "8ef130f9ec27973f7b49e20c5a3b9134ca33026c", "lessThan": "91be54849d5392050f5b847b42bd5e6221551ac8", "status": "affected", "versionType": "git" }, { "version": "8ef130f9ec27973f7b49e20c5a3b9134ca33026c", "lessThan": "e037baee16e0b9ace7e730888fcae9cec11daff2", "status": "affected", "versionType": "git" }, { "version": "8ef130f9ec27973f7b49e20c5a3b9134ca33026c", "lessThan": "4b83bc6f87eedab4599b0123e572a422689444be", "status": "affected", "versionType": "git" }, { "version": "8ef130f9ec27973f7b49e20c5a3b9134ca33026c", "lessThan": "5109607a4ece7cd8536172bf7549eb4dce1f3576", "status": "affected", "versionType": "git" }, { "version": "8ef130f9ec27973f7b49e20c5a3b9134ca33026c", "lessThan": "b7ab9161cf5ddc42a288edf9d1a61f3bdffe17c7", "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/cifs/smbdirect.c" ], "versions": [ { "version": "4.16", "status": "affected" }, { "version": "0", "lessThan": "4.16", "status": "unaffected", "versionType": "semver" }, { "version": "4.19.272", "lessThanOrEqual": "4.19.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.4.231", "lessThanOrEqual": "5.4.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.166", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.91", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.9", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.2", "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": "4.16", "versionEndExcluding": "4.19.272" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "5.4.231" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "5.10.166" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "5.15.91" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "6.1.9" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "6.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/a9640c0b268405f2540e8203a545e930ea88bb7d" }, { "url": "https://git.kernel.org/stable/c/91be54849d5392050f5b847b42bd5e6221551ac8" }, { "url": "https://git.kernel.org/stable/c/e037baee16e0b9ace7e730888fcae9cec11daff2" }, { "url": "https://git.kernel.org/stable/c/4b83bc6f87eedab4599b0123e572a422689444be" }, { "url": "https://git.kernel.org/stable/c/5109607a4ece7cd8536172bf7549eb4dce1f3576" }, { "url": "https://git.kernel.org/stable/c/b7ab9161cf5ddc42a288edf9d1a61f3bdffe17c7" } ], "title": "cifs: Fix oops due to uncleared server->smbd_conn in reconnect", "x_generator": { "engine": "bippy-1.2.0" } } } }