{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2022-48935", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-08-21T06:06:23.299Z", "datePublished": "2024-08-22T03:31:29.598Z", "dateUpdated": "2026-08-05T08:53:00.192Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T08:53:00.192Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_tables: unregister flowtable hooks on netns exit\n\nUnregister flowtable hooks before they are releases via\nnf_tables_flowtable_destroy() otherwise hook core reports UAF.\n\nBUG: KASAN: use-after-free in nf_hook_entries_grow+0x5a7/0x700 net/netfilter/core.c:142 net/netfilter/core.c:142\nRead of size 4 at addr ffff8880736f7438 by task syz-executor579/3666\n\nCPU: 0 PID: 3666 Comm: syz-executor579 Not tainted 5.16.0-rc5-syzkaller #0\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011\nCall Trace:\n \n __dump_stack lib/dump_stack.c:88 [inline]\n __dump_stack lib/dump_stack.c:88 [inline] lib/dump_stack.c:106\n dump_stack_lvl+0x1dc/0x2d8 lib/dump_stack.c:106 lib/dump_stack.c:106\n print_address_description+0x65/0x380 mm/kasan/report.c:247 mm/kasan/report.c:247\n __kasan_report mm/kasan/report.c:433 [inline]\n __kasan_report mm/kasan/report.c:433 [inline] mm/kasan/report.c:450\n kasan_report+0x19a/0x1f0 mm/kasan/report.c:450 mm/kasan/report.c:450\n nf_hook_entries_grow+0x5a7/0x700 net/netfilter/core.c:142 net/netfilter/core.c:142\n __nf_register_net_hook+0x27e/0x8d0 net/netfilter/core.c:429 net/netfilter/core.c:429\n nf_register_net_hook+0xaa/0x180 net/netfilter/core.c:571 net/netfilter/core.c:571\n nft_register_flowtable_net_hooks+0x3c5/0x730 net/netfilter/nf_tables_api.c:7232 net/netfilter/nf_tables_api.c:7232\n nf_tables_newflowtable+0x2022/0x2cf0 net/netfilter/nf_tables_api.c:7430 net/netfilter/nf_tables_api.c:7430\n nfnetlink_rcv_batch net/netfilter/nfnetlink.c:513 [inline]\n nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:634 [inline]\n nfnetlink_rcv_batch net/netfilter/nfnetlink.c:513 [inline] net/netfilter/nfnetlink.c:652\n nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:634 [inline] net/netfilter/nfnetlink.c:652\n nfnetlink_rcv+0x10e6/0x2550 net/netfilter/nfnetlink.c:652 net/netfilter/nfnetlink.c:652\n\n__nft_release_hook() calls nft_unregister_flowtable_net_hooks() which\nonly unregisters the hooks, then after RCU grace period, it is\nguaranteed that no packets add new entries to the flowtable (no flow\noffload rules and flowtable hooks are reachable from packet path), so it\nis safe to call nf_flow_table_free() which cleans up the remaining\nentries from the flowtable (both software and hardware) and it unbinds\nthe flow_block." } ], "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 vulnerability is reached via nfnetlink/nftables netlink messages (nf_tables_newflowtable and table teardown), which require local process access rather than remote packet delivery.\nAC:L - An attacker fully controls the trigger sequence by creating an owned table with a flowtable, closing the netlink socket (or exiting the netns), then reclaiming freed objects and sending packets or registering new hooks—no conditions outside attacker control.\nPR:L - nftables requires CAP_NET_ADMIN checked via netlink_net_capable against the network namespace's user_ns, which an unprivileged user obtains through user+network namespaces (unshare -Urn).\nUI:N - Exploitation requires no victim action; the attacker creates the flowtable, triggers teardown, and drives the UAF themselves.\nS:U - Impact is confined to the local kernel privilege boundary (local privilege escalation / memory corruption), with no VM, IOMMU, or cross-authority escape.\nC:H - The bug is a use-after-free of nft_hook and nf_flowtable objects still referenced from live netdev hook entries (priv=&flowtable->data), enabling heap spray and arbitrary kernel read primitives.\nI:H - The dangling flowtable hook remains callable on the packet path with a freed priv pointer, so reclaiming that object yields write/control-flow hijack primitives suitable for code execution.\nA:H - Accessing the freed hook ops or flowtable from nf_hook_entries_grow or the ingress hook path causes kernel oops/panic, as demonstrated by the KASAN UAF report." } ] } ], "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": "ff4bf2f42a40e7dff28379f085b64df322c70b45", "lessThan": "e51f30826bc5384801df98d76109c94953d1df64", "status": "affected", "versionType": "git" }, { "version": "ff4bf2f42a40e7dff28379f085b64df322c70b45", "lessThan": "8ffb8ac3448845f65634889b051bd65e4dee484b", "status": "affected", "versionType": "git" }, { "version": "ff4bf2f42a40e7dff28379f085b64df322c70b45", "lessThan": "b4fcc081e527aa2ce12e956912fc47e251f6bd27", "status": "affected", "versionType": "git" }, { "version": "ff4bf2f42a40e7dff28379f085b64df322c70b45", "lessThan": "6069da443bf65f513bb507bb21e2f87cfb1ad0b6", "status": "affected", "versionType": "git" } ] }, { "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": "5.5", "status": "affected" }, { "version": "0", "lessThan": "5.5", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.198", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.26", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.16.12", "lessThanOrEqual": "5.16.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.17", "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": "5.5", "versionEndExcluding": "5.10.198" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.5", "versionEndExcluding": "5.15.26" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.5", "versionEndExcluding": "5.16.12" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.5", "versionEndExcluding": "5.17" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/e51f30826bc5384801df98d76109c94953d1df64" }, { "url": "https://git.kernel.org/stable/c/8ffb8ac3448845f65634889b051bd65e4dee484b" }, { "url": "https://git.kernel.org/stable/c/b4fcc081e527aa2ce12e956912fc47e251f6bd27" }, { "url": "https://git.kernel.org/stable/c/6069da443bf65f513bb507bb21e2f87cfb1ad0b6" } ], "title": "netfilter: nf_tables: unregister flowtable hooks on netns exit", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "id": "CVE-2022-48935", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "partial" } ], "version": "2.0.3", "timestamp": "2024-09-10T15:32:37.130969Z" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2024-09-12T17:33:09.712Z" } } ] } }