{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2024-42109", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-07-29T15:50:41.176Z", "datePublished": "2024-07-30T07:46:04.194Z", "dateUpdated": "2026-08-05T11:35:41.134Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T11:35:41.134Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_tables: unconditionally flush pending work before notifier\n\nsyzbot reports:\n\nKASAN: slab-uaf in nft_ctx_update include/net/netfilter/nf_tables.h:1831\nKASAN: slab-uaf in nft_commit_release net/netfilter/nf_tables_api.c:9530\nKASAN: slab-uaf int nf_tables_trans_destroy_work+0x152b/0x1750 net/netfilter/nf_tables_api.c:9597\nRead of size 2 at addr ffff88802b0051c4 by task kworker/1:1/45\n[..]\nWorkqueue: events nf_tables_trans_destroy_work\nCall Trace:\n nft_ctx_update include/net/netfilter/nf_tables.h:1831 [inline]\n nft_commit_release net/netfilter/nf_tables_api.c:9530 [inline]\n nf_tables_trans_destroy_work+0x152b/0x1750 net/netfilter/nf_tables_api.c:9597\n\nProblem is that the notifier does a conditional flush, but its possible\nthat the table-to-be-removed is still referenced by transactions being\nprocessed by the worker, so we need to flush unconditionally.\n\nWe could make the flush_work depend on whether we found a table to delete\nin nf-next to avoid the flush for most cases.\n\nAFAICS this problem is only exposed in nf-next, with\ncommit e169285f8c56 (\"netfilter: nf_tables: do not store nft_ctx in transaction objects\"),\nwith this commit applied there is an unconditional fetch of\ntable->family which is whats triggering the above splat." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The vulnerable path is entered only through `sendmsg()`/`close()` on a local `AF_NETLINK`/`NETLINK_NETFILTER` socket handled by `nfnetlink_rcv_msg()`; the notifier `nft_rcv_nl_event()` fires on local socket release. There is no remote or adjacent-network route into nf_tables transaction teardown.\nAC:L - The attacker drives both halves of the race — issuing the nftables commit that queues transactions to `nf_tables_destroy_list` and schedule `trans_destroy_work`, then closing the owning netlink socket — and the worker's `list_splice_init()` plus `synchronize_rcu()` leaves a millisecond-wide window in which `list_empty()` is falsely true. The sequence is deterministic to set up and infinitely retryable, and syzbot produced a working reproducer.\nPR:L - The only check is `netlink_net_capable(skb, CAP_NET_ADMIN)`, which is `ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)` — satisfied by any unprivileged user via `unshare -Urn` on distros with unprivileged user namespaces enabled. No real root in the init namespace is required.\nUI:N - The attacker performs the entire sequence — table creation with `NFT_TABLE_F_OWNER`, the delete commit, and the socket close — from its own process with no victim involvement.\nS:U - The freed object and all its dereferences live in kernel memory within the same security authority; there is no VM, IOMMU, or sandbox boundary crossed.\nC:H - This is a confirmed slab use-after-free read of the `nft_table` object (`kmalloc-cg-*`, syzbot: \"Read of size 2\"); an attacker can reoccupy the freed slot by heap spraying and have the worker read attacker-chosen data, including the `ctx->table->name` pointer consumed by `nft_compat`, yielding an information-disclosure primitive.\nI:H - The dangling `trans->ctx.table` is fed to `nft_set_destroy()`, `nf_tables_chain_destroy()`, `nft_obj_destroy()` and every expression `->destroy()` callback, so a reclaimed slot lets the attacker steer subsequent frees, refcount decrements, and function-pointer-driven teardown — a classic UAF path to controlled writes and control-flow hijack.\nA:H - Even unexploited, the use-after-free corrupts kernel state inside a workqueue context and reliably produces an oops/panic, as demonstrated by the syzbot KASAN splat in `nf_tables_trans_destroy_work`." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/netfilter/nf_tables_api.c" ], "versions": [ { "version": "f22954f8c58fd5f5489f5980796914e306757e77", "lessThan": "3325628cb36b7f216c5716e7b5124d9dc81199e4", "status": "affected", "versionType": "git" }, { "version": "41841b585e53babdfb0fa6fdfa54f6d7c28c1206", "lessThan": "4c06c13317b9a08decedcd7aaf706691e336277c", "status": "affected", "versionType": "git" }, { "version": "2c9f0293280e258606e54ed2b96fa71498432eae", "lessThan": "55a40406aac555defe9bdd0adec9508116ce7cb1", "status": "affected", "versionType": "git" }, { "version": "2c9f0293280e258606e54ed2b96fa71498432eae", "lessThan": "09e650c3a3a7d804430260510534ccbf71c75b2e", "status": "affected", "versionType": "git" }, { "version": "2c9f0293280e258606e54ed2b96fa71498432eae", "lessThan": "9f6958ba2e902f9820c594869bd710ba74b7c4c0", "status": "affected", "versionType": "git" }, { "version": "4167aa477abcf62b0dfda51f3513280fa73cd588", "status": "affected", "versionType": "git" }, { "version": "5.15.129", "lessThan": "5.15.163", "status": "affected", "versionType": "semver" }, { "version": "6.1.50", "lessThan": "6.1.98", "status": "affected", "versionType": "semver" }, { "version": "6.4.13", "lessThan": "6.5", "status": "affected", "versionType": "semver" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/netfilter/nf_tables_api.c" ], "versions": [ { "version": "6.5", "status": "affected" }, { "version": "0", "lessThan": "6.5", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.163", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.98", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.39", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.9.9", "lessThanOrEqual": "6.9.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.10", "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": "5.15.129", "versionEndExcluding": "5.15.163" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1.50", "versionEndExcluding": "6.1.98" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.5", "versionEndExcluding": "6.6.39" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.5", "versionEndExcluding": "6.9.9" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.5", "versionEndExcluding": "6.10" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.4.13" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/3325628cb36b7f216c5716e7b5124d9dc81199e4" }, { "url": "https://git.kernel.org/stable/c/4c06c13317b9a08decedcd7aaf706691e336277c" }, { "url": "https://git.kernel.org/stable/c/55a40406aac555defe9bdd0adec9508116ce7cb1" }, { "url": "https://git.kernel.org/stable/c/09e650c3a3a7d804430260510534ccbf71c75b2e" }, { "url": "https://git.kernel.org/stable/c/9f6958ba2e902f9820c594869bd710ba74b7c4c0" } ], "title": "netfilter: nf_tables: unconditionally flush pending work before notifier", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "title": "CVE Program Container", "references": [ { "url": "https://git.kernel.org/stable/c/3325628cb36b7f216c5716e7b5124d9dc81199e4", "tags": [ "x_transferred" ] }, { "url": "https://git.kernel.org/stable/c/4c06c13317b9a08decedcd7aaf706691e336277c", "tags": [ "x_transferred" ] }, { "url": "https://git.kernel.org/stable/c/55a40406aac555defe9bdd0adec9508116ce7cb1", "tags": [ "x_transferred" ] }, { "url": "https://git.kernel.org/stable/c/09e650c3a3a7d804430260510534ccbf71c75b2e", "tags": [ "x_transferred" ] }, { "url": "https://git.kernel.org/stable/c/9f6958ba2e902f9820c594869bd710ba74b7c4c0", "tags": [ "x_transferred" ] }, { "url": "https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html" } ], "providerMetadata": { "orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2025-11-03T22:01:44.106Z" } }, { "metrics": [ { "other": { "type": "ssvc", "content": { "id": "CVE-2024-42109", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "partial" } ], "version": "2.0.3", "timestamp": "2024-09-10T16:17:36.218121Z" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2024-09-11T17:33:06.893Z" } } ] } }