{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2024-35861", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-05-17T13:50:33.107Z", "datePublished": "2024-05-19T08:34:20.364Z", "dateUpdated": "2026-08-05T11:30:25.104Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T11:30:25.104Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: fix potential UAF in cifs_signal_cifsd_for_reconnect()\n\nSkip sessions that are being teared down (status == SES_EXITING) to\navoid UAF." } ], "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 vulnerable list walk is entered directly from data supplied by the remote SMB server — `mark_for_reconnect_if_needed()` fires when the server's DFS referral targets change, and `tree_connect_dfs_target()` fires from `smb2_reconnect()` when server-driven tree connects fail with a changed `leaf_fullpath`. The same remote peer also controls the width of the race window by stalling its SMB2 LOGOFF/TREE_DISCONNECT reply.\nAC:L - The attacker drives both sides of the race: the SES_EXITING-while-still-linked window spans blocking SMB round-trips that a malicious server can hold open until the SMB timeout, while referral churn or repeated forced reconnects re-enter the walk at unbounded rate. No condition depends on state outside the attacker's influence.\nPR:N - A malicious or compromised SMB server holds no privilege on the victim client — the client authenticates to the server, not the reverse — so no credentials on the vulnerable component are needed. The alternate local path via `CIFS_GENL_CMD_SWN_NOTIFY` also carries no `GENL_ADMIN_PERM` and is usable by any unprivileged user.\nUI:N - On an already-mounted enterprise SMB share (the normal automounted/persistent case), the DFS refresh worker and reconnect paths run on their own and session teardowns occur automatically via `cifs_prune_tlinks` and DFS failover. No victim action is required at exploitation time.\nS:U - The use-after-free corrupts kernel heap memory within the same kernel security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - The walk reads `ses->chan_count` and `ses->chans[i].server` plus `server->tcpStatus` out of a freed/reallocated `cifs_ses`, and a use-after-free on this object gives control over freed-slab contents, which is leverageable into an arbitrary kernel read primitive against `cifs_ses` state including session and encryption keys.\nI:H - The walk writes into the stale objects — acquiring `ses->chan_lock` and `ses->chans[i].server->srv_lock`, then storing `CifsNeedReconnect` into `tcpStatus`. Since the teardown path NULLs `chans[i].server` without `chan_lock` and never lowers `chan_count`, a sprayed replacement object yields a spinlock acquire plus a store at an attacker-chosen address, i.e. a write primitive usable for control-flow hijack.\nA:H - Dereferencing a freed `TCP_Server_Info` and taking `srv_lock` on reclaimed memory reliably produces slab corruption, a spinlock lockup, or an oops/panic, and the trigger can be repeated indefinitely by the remote server." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/smb/client/connect.c" ], "versions": [ { "version": "dca65818c80cf06e0f08ba2cf94060a5236e73c2", "lessThan": "7e8360ac8774e19b0b25f44fff84a105bb2417e4", "status": "affected", "versionType": "git" }, { "version": "dca65818c80cf06e0f08ba2cf94060a5236e73c2", "lessThan": "2cfff21732132e363b4cc275d63ea98f1af726c1", "status": "affected", "versionType": "git" }, { "version": "dca65818c80cf06e0f08ba2cf94060a5236e73c2", "lessThan": "f9a96a7ad1e8d25dc6662bc7552e0752de74a20d", "status": "affected", "versionType": "git" }, { "version": "dca65818c80cf06e0f08ba2cf94060a5236e73c2", "lessThan": "e0e50401cc3921c9eaf1b0e667db174519ea939f", "status": "affected", "versionType": "git" }, { "version": "dd9ccff8c8980bf9ea7f25e83eeb28154f902920", "status": "affected", "versionType": "git" }, { "version": "5.17.2", "lessThan": "5.18", "status": "affected", "versionType": "semver" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/smb/client/connect.c" ], "versions": [ { "version": "5.18", "status": "affected" }, { "version": "0", "lessThan": "5.18", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.85", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.26", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.8.5", "lessThanOrEqual": "6.8.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.9", "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": "5.18", "versionEndExcluding": "6.1.85" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.18", "versionEndExcluding": "6.6.26" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.18", "versionEndExcluding": "6.8.5" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.18", "versionEndExcluding": "6.9" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.17.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/7e8360ac8774e19b0b25f44fff84a105bb2417e4" }, { "url": "https://git.kernel.org/stable/c/2cfff21732132e363b4cc275d63ea98f1af726c1" }, { "url": "https://git.kernel.org/stable/c/f9a96a7ad1e8d25dc6662bc7552e0752de74a20d" }, { "url": "https://git.kernel.org/stable/c/e0e50401cc3921c9eaf1b0e667db174519ea939f" } ], "title": "smb: client: fix potential UAF in cifs_signal_cifsd_for_reconnect()", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "providerMetadata": { "orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2024-08-02T03:21:48.592Z" }, "title": "CVE Program Container", "references": [ { "url": "https://git.kernel.org/stable/c/7e8360ac8774e19b0b25f44fff84a105bb2417e4", "tags": [ "x_transferred" ] }, { "url": "https://git.kernel.org/stable/c/2cfff21732132e363b4cc275d63ea98f1af726c1", "tags": [ "x_transferred" ] }, { "url": "https://git.kernel.org/stable/c/f9a96a7ad1e8d25dc6662bc7552e0752de74a20d", "tags": [ "x_transferred" ] }, { "url": "https://git.kernel.org/stable/c/e0e50401cc3921c9eaf1b0e667db174519ea939f", "tags": [ "x_transferred" ] } ] }, { "metrics": [ { "other": { "type": "ssvc", "content": { "id": "CVE-2024-35861", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "partial" } ], "version": "2.0.3", "timestamp": "2024-09-10T15:41:30.759863Z" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2024-09-11T17:33:17.503Z" } } ] } }