{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2024-50047", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-10-21T12:17:06.071Z", "datePublished": "2024-10-21T19:39:44.430Z", "dateUpdated": "2026-08-05T11:41:16.159Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T11:41:16.159Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: fix UAF in async decryption\n\nDoing an async decryption (large read) crashes with a\nslab-use-after-free way down in the crypto API.\n\nReproducer:\n # mount.cifs -o ...,seal,esize=1 //srv/share /mnt\n # dd if=/mnt/largefile of=/dev/null\n ...\n [ 194.196391] ==================================================================\n [ 194.196844] BUG: KASAN: slab-use-after-free in gf128mul_4k_lle+0xc1/0x110\n [ 194.197269] Read of size 8 at addr ffff888112bd0448 by task kworker/u77:2/899\n [ 194.197707]\n [ 194.197818] CPU: 12 UID: 0 PID: 899 Comm: kworker/u77:2 Not tainted 6.11.0-lku-00028-gfca3ca14a17a-dirty #43\n [ 194.198400] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.2-3-gd478f380-prebuilt.qemu.org 04/01/2014\n [ 194.199046] Workqueue: smb3decryptd smb2_decrypt_offload [cifs]\n [ 194.200032] Call Trace:\n [ 194.200191] \n [ 194.200327] dump_stack_lvl+0x4e/0x70\n [ 194.200558] ? gf128mul_4k_lle+0xc1/0x110\n [ 194.200809] print_report+0x174/0x505\n [ 194.201040] ? __pfx__raw_spin_lock_irqsave+0x10/0x10\n [ 194.201352] ? srso_return_thunk+0x5/0x5f\n [ 194.201604] ? __virt_addr_valid+0xdf/0x1c0\n [ 194.201868] ? gf128mul_4k_lle+0xc1/0x110\n [ 194.202128] kasan_report+0xc8/0x150\n [ 194.202361] ? gf128mul_4k_lle+0xc1/0x110\n [ 194.202616] gf128mul_4k_lle+0xc1/0x110\n [ 194.202863] ghash_update+0x184/0x210\n [ 194.203103] shash_ahash_update+0x184/0x2a0\n [ 194.203377] ? __pfx_shash_ahash_update+0x10/0x10\n [ 194.203651] ? srso_return_thunk+0x5/0x5f\n [ 194.203877] ? crypto_gcm_init_common+0x1ba/0x340\n [ 194.204142] gcm_hash_assoc_remain_continue+0x10a/0x140\n [ 194.204434] crypt_message+0xec1/0x10a0 [cifs]\n [ 194.206489] ? __pfx_crypt_message+0x10/0x10 [cifs]\n [ 194.208507] ? srso_return_thunk+0x5/0x5f\n [ 194.209205] ? srso_return_thunk+0x5/0x5f\n [ 194.209925] ? srso_return_thunk+0x5/0x5f\n [ 194.210443] ? srso_return_thunk+0x5/0x5f\n [ 194.211037] decrypt_raw_data+0x15f/0x250 [cifs]\n [ 194.212906] ? __pfx_decrypt_raw_data+0x10/0x10 [cifs]\n [ 194.214670] ? srso_return_thunk+0x5/0x5f\n [ 194.215193] smb2_decrypt_offload+0x12a/0x6c0 [cifs]\n\nThis is because TFM is being used in parallel.\n\nFix this by allocating a new AEAD TFM for async decryption, but keep\nthe existing one for synchronous READ cases (similar to what is done\nin smb3_calc_signature()).\n\nAlso remove the calls to aead_request_set_callback() and\ncrypto_wait_req() since it's always going to be a synchronous operation." } ], "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 occurs while the CIFS/SMB3 client decrypts transform-encrypted READ responses received from a remote SMB server over TCP/445, on data (transform header, message size, nonce, ciphertext) fully supplied by that peer. A malicious, compromised, or MITM'd server drives the vulnerable path remotely, and can itself force encryption on via SMB2_SESSION_FLAG_ENCRYPT_DATA / SHI1005_FLAGS_ENCRYPT_DATA.\nAC:L - The server controls both sides of the race by pipelining multiple large encrypted READ responses, guaranteeing concurrent smb3decryptd workers on the shared TFM; the commit's reproducer is an ordinary `dd` of a large file, so the corruption occurs deterministically in normal operation rather than requiring a rare window.\nPR:N - The remote SMB server needs no privileges on the client to send the encrypted read responses that trigger the parallel TFM use, and locally any unprivileged user with read access to the mounted share can issue the concurrent large reads.\nUI:N - No victim action is needed beyond an already-established mount; the UAF fires during routine background file reads on the existing connection.\nS:U - The corruption is confined to kernel memory within the same security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - Freed slab memory (the gf128mul ghash key table and TFM context) is read by the crypto engine, and heap grooming lets an attacker place chosen objects there for arbitrary kernel memory disclosure; cross-worker key clobbering can also expose data decrypted under the wrong session key.\nI:H - The crypto transform writes into the freed, reallocated slab object, giving a heap write primitive over attacker-groomable memory that is leveragable for control-flow hijack, and concurrent setkey/setauthsize corrupt in-flight crypto state.\nA:H - The use-after-free reliably produces a KASAN slab-use-after-free and kernel oops in the smb3decryptd workqueue, panicking or hanging the client; it can be retriggered at will." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/smb/client/smb2ops.c", "fs/smb/client/smb2pdu.c" ], "versions": [ { "version": "35cf94a397280b9e27576ac1480f631bdd3e7b70", "lessThan": "8f14a476abba13144df5434871a7225fd29af633", "status": "affected", "versionType": "git" }, { "version": "35cf94a397280b9e27576ac1480f631bdd3e7b70", "lessThan": "ef51c0d544b1518b35364480317ab6d3468f205d", "status": "affected", "versionType": "git" }, { "version": "35cf94a397280b9e27576ac1480f631bdd3e7b70", "lessThan": "bce966530fd5542bbb422cb45ecb775f7a1a6bc3", "status": "affected", "versionType": "git" }, { "version": "35cf94a397280b9e27576ac1480f631bdd3e7b70", "lessThan": "0809fb86ad13b29e1d6d491364fc7ea4fb545995", "status": "affected", "versionType": "git" }, { "version": "35cf94a397280b9e27576ac1480f631bdd3e7b70", "lessThan": "538c26d9bf70c90edc460d18c81008a4e555925a", "status": "affected", "versionType": "git" }, { "version": "35cf94a397280b9e27576ac1480f631bdd3e7b70", "lessThan": "b0abcd65ec545701b8793e12bc27dc98042b151a", "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/client/smb2ops.c", "fs/smb/client/smb2pdu.c" ], "versions": [ { "version": "5.4", "status": "affected" }, { "version": "0", "lessThan": "5.4", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.237", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.181", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.128", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.57", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.11.4", "lessThanOrEqual": "6.11.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12", "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": "5.4", "versionEndExcluding": "5.10.237" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.4", "versionEndExcluding": "5.15.181" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.4", "versionEndExcluding": "6.1.128" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.4", "versionEndExcluding": "6.6.57" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.4", "versionEndExcluding": "6.11.4" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.4", "versionEndExcluding": "6.12" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/8f14a476abba13144df5434871a7225fd29af633" }, { "url": "https://git.kernel.org/stable/c/ef51c0d544b1518b35364480317ab6d3468f205d" }, { "url": "https://git.kernel.org/stable/c/bce966530fd5542bbb422cb45ecb775f7a1a6bc3" }, { "url": "https://git.kernel.org/stable/c/0809fb86ad13b29e1d6d491364fc7ea4fb545995" }, { "url": "https://git.kernel.org/stable/c/538c26d9bf70c90edc460d18c81008a4e555925a" }, { "url": "https://git.kernel.org/stable/c/b0abcd65ec545701b8793e12bc27dc98042b151a" } ], "title": "smb: client: fix UAF in async decryption", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "id": "CVE-2024-50047", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "partial" } ], "version": "2.0.3", "timestamp": "2024-10-22T13:23:59.456851Z" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2024-10-22T13:28:43.459Z" } }, { "title": "CVE Program Container", "references": [ { "url": "https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html" }, { "url": "https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html" } ], "providerMetadata": { "orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2025-11-03T20:43:16.334Z" } } ] } }