{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-43016", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-05-01T14:12:55.974Z", "datePublished": "2026-05-01T14:15:20.887Z", "dateUpdated": "2026-08-05T12:25:16.418Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:25:16.418Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: sockmap: Fix use-after-free of sk->sk_socket in sk_psock_verdict_data_ready().\n\nsyzbot reported use-after-free of AF_UNIX socket's sk->sk_socket\nin sk_psock_verdict_data_ready(). [0]\n\nIn unix_stream_sendmsg(), the peer socket's ->sk_data_ready() is\ncalled after dropping its unix_state_lock().\n\nAlthough the sender socket holds the peer's refcount, it does not\nprevent the peer's sock_orphan(), and the peer's sk_socket might\nbe freed after one RCU grace period.\n\nLet's fetch the peer's sk->sk_socket and sk->sk_socket->ops under\nRCU in sk_psock_verdict_data_ready().\n\n[0]:\nBUG: KASAN: slab-use-after-free in sk_psock_verdict_data_ready+0xec/0x590 net/core/skmsg.c:1278\nRead of size 8 at addr ffff8880594da860 by task syz.4.1842/11013\n\nCPU: 1 UID: 0 PID: 11013 Comm: syz.4.1842 Not tainted syzkaller #0 PREEMPT(full)\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026\nCall Trace:\n \n dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120\n print_address_description mm/kasan/report.c:378 [inline]\n print_report+0xba/0x230 mm/kasan/report.c:482\n kasan_report+0x117/0x150 mm/kasan/report.c:595\n sk_psock_verdict_data_ready+0xec/0x590 net/core/skmsg.c:1278\n unix_stream_sendmsg+0x8a3/0xe80 net/unix/af_unix.c:2482\n sock_sendmsg_nosec net/socket.c:721 [inline]\n __sock_sendmsg net/socket.c:736 [inline]\n ____sys_sendmsg+0x972/0x9f0 net/socket.c:2585\n ___sys_sendmsg+0x2a5/0x360 net/socket.c:2639\n __sys_sendmsg net/socket.c:2671 [inline]\n __do_sys_sendmsg net/socket.c:2676 [inline]\n __se_sys_sendmsg net/socket.c:2674 [inline]\n __x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2674\n do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]\n do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\nRIP: 0033:0x7facf899c819\nCode: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48\nRSP: 002b:00007facf9827028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e\nRAX: ffffffffffffffda RBX: 00007facf8c15fa0 RCX: 00007facf899c819\nRDX: 0000000000000000 RSI: 0000200000000500 RDI: 0000000000000004\nRBP: 00007facf8a32c91 R08: 0000000000000000 R09: 0000000000000000\nR10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000\nR13: 00007facf8c16038 R14: 00007facf8c15fa0 R15: 00007ffd41b01c78\n \n\nAllocated by task 11013:\n kasan_save_stack mm/kasan/common.c:57 [inline]\n kasan_save_track+0x3e/0x80 mm/kasan/common.c:78\n unpoison_slab_object mm/kasan/common.c:340 [inline]\n __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366\n kasan_slab_alloc include/linux/kasan.h:253 [inline]\n slab_post_alloc_hook mm/slub.c:4538 [inline]\n slab_alloc_node mm/slub.c:4866 [inline]\n kmem_cache_alloc_lru_noprof+0x2b8/0x640 mm/slub.c:4885\n sock_alloc_inode+0x28/0xc0 net/socket.c:316\n alloc_inode+0x6a/0x1b0 fs/inode.c:347\n new_inode_pseudo include/linux/fs.h:3003 [inline]\n sock_alloc net/socket.c:631 [inline]\n __sock_create+0x12d/0x9d0 net/socket.c:1562\n sock_create net/socket.c:1656 [inline]\n __sys_socketpair+0x1c4/0x560 net/socket.c:1803\n __do_sys_socketpair net/socket.c:1856 [inline]\n __se_sys_socketpair net/socket.c:1853 [inline]\n __x64_sys_socketpair+0x9b/0xb0 net/socket.c:1853\n do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]\n do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\n\nFreed by task 15:\n kasan_save_stack mm/kasan/common.c:57 [inline]\n kasan_save_track+0x3e/0x80 mm/kasan/common.c:78\n kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584\n poison_slab_object mm/kasan/common.c:253 [inline]\n __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285\n kasan_slab_free include/linux/kasan.h:235 [inline]\n slab_free_hook mm/slub.c:2685 [inline]\n slab_free mm/slub.c:6165 [inline]\n kmem_cache_free+0x187/0x630 mm/slub.c:6295\n rcu_do_batch kernel/rcu/tree.c:\n---truncated---" } ], "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 callback is reached through local BPF sockmap setup and local AF_UNIX send/close activity, not by unauthenticated network packets alone.\nAC:L - The attacker can create the socketpair, install the sockmap verdict path, and race sendmsg against close/orphaning of the peer socket; both sides of the race are attacker-controlled.\nPR:L - Creating and attaching the required sockmap/SK_SKB or SK_MSG BPF objects requires BPF/CAP_NET_ADMIN-style privileges, but these can be available to a low-privileged local user in delegated or user-namespace BPF deployments; choosing the higher severity option gives PR:L.\nUI:N - No victim action is needed after the attacker has local execution and the required BPF access; triggering is done with attacker-controlled syscalls.\nS:U - The impact is within the kernel security authority and represents ordinary kernel memory corruption or privilege escalation, not a cross-scope boundary such as guest-to-host escape.\nC:H - This is a use-after-free of the socket object used to fetch proto_ops, and kernel UAFs can be shaped into information disclosure primitives.\nI:H - The stale socket pointer can lead to use of attacker-influenced freed memory and function-pointer-oriented control flow, making arbitrary modification or code execution defensible.\nA:H - The reported KASAN splat demonstrates a kernel use-after-free reachable from sendmsg, and repeated triggering can crash or destabilize the kernel." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/core/skmsg.c" ], "versions": [ { "version": "c63829182c37c2d6d0608976d15fa61ebebe9e6b", "lessThan": "8d597e3e74027900ffa81b8ff47ab51999a3e110", "status": "affected", "versionType": "git" }, { "version": "c63829182c37c2d6d0608976d15fa61ebebe9e6b", "lessThan": "68187f18a89be4b6237d28ae1313b5adf76238c6", "status": "affected", "versionType": "git" }, { "version": "c63829182c37c2d6d0608976d15fa61ebebe9e6b", "lessThan": "18861f87a043e78b1f901cae4237e755ed7ef095", "status": "affected", "versionType": "git" }, { "version": "c63829182c37c2d6d0608976d15fa61ebebe9e6b", "lessThan": "af95bc39a83d82ae6ad253986335037256888b3f", "status": "affected", "versionType": "git" }, { "version": "c63829182c37c2d6d0608976d15fa61ebebe9e6b", "lessThan": "ad8391d37f334ee73ba91926f8b4e4cf6d31ea04", "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/core/skmsg.c" ], "versions": [ { "version": "5.15", "status": "affected" }, { "version": "0", "lessThan": "5.15", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.134", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.81", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.22", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.19.12", "lessThanOrEqual": "6.19.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.0", "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", "versionEndExcluding": "6.6.134" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.12.81" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.18.22" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.19.12" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "7.0" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/8d597e3e74027900ffa81b8ff47ab51999a3e110" }, { "url": "https://git.kernel.org/stable/c/68187f18a89be4b6237d28ae1313b5adf76238c6" }, { "url": "https://git.kernel.org/stable/c/18861f87a043e78b1f901cae4237e755ed7ef095" }, { "url": "https://git.kernel.org/stable/c/af95bc39a83d82ae6ad253986335037256888b3f" }, { "url": "https://git.kernel.org/stable/c/ad8391d37f334ee73ba91926f8b4e4cf6d31ea04" } ], "title": "bpf: sockmap: Fix use-after-free of sk->sk_socket in sk_psock_verdict_data_ready().", "x_generator": { "engine": "bippy-1.2.0" } } } }