GHSA-2F72-2CHX-Q8P6
Vulnerability from github – Published: 2026-06-24 18:32 – Updated: 2026-06-30 03:37In the Linux kernel, the following vulnerability has been resolved:
bpf, sockmap: Take state lock for af_unix iter
When a BPF iterator program updates a sockmap, there is a race condition in
unix_stream_bpf_update_proto() where the peer pointer can become stale[1]
during a state transition TCP_ESTABLISHED -> TCP_CLOSE.
CPU0 bpf CPU1 close
-------- ----------
// unix_stream_bpf_update_proto() sk_pair = unix_peer(sk) if (unlikely(!sk_pair)) return -EINVAL; // unix_release_sock() skpair = unix_peer(sk); unix_peer(sk) = NULL; sock_put(skpair) sock_hold(sk_pair) // UaF
More practically, this fix guarantees that the iterator program is consistently provided with a unix socket that remains stable during iterator execution.
[1]: BUG: KASAN: slab-use-after-free in unix_stream_bpf_update_proto+0x155/0x490 Write of size 4 at addr ffff8881178c9a00 by task test_progs/2231 Call Trace: dump_stack_lvl+0x5d/0x80 print_report+0x170/0x4f3 kasan_report+0xe4/0x1c0 kasan_check_range+0x125/0x200 unix_stream_bpf_update_proto+0x155/0x490 sock_map_link+0x71c/0xec0 sock_map_update_common+0xbc/0x600 sock_map_update_elem+0x19a/0x1f0 bpf_prog_bbbf56096cdd4f01_selective_dump_unix+0x20c/0x217 bpf_iter_run_prog+0x21e/0xae0 bpf_iter_unix_seq_show+0x1e0/0x2a0 bpf_seq_read+0x42c/0x10d0 vfs_read+0x171/0xb20 ksys_read+0xff/0x200 do_syscall_64+0xf7/0x5e0 entry_SYSCALL_64_after_hwframe+0x76/0x7e
Allocated by task 2236: kasan_save_stack+0x30/0x50 kasan_save_track+0x14/0x30 __kasan_slab_alloc+0x63/0x80 kmem_cache_alloc_noprof+0x1d5/0x680 sk_prot_alloc+0x59/0x210 sk_alloc+0x34/0x470 unix_create1+0x86/0x8a0 unix_stream_connect+0x318/0x15b0 __sys_connect+0xfd/0x130 __x64_sys_connect+0x72/0xd0 do_syscall_64+0xf7/0x5e0 entry_SYSCALL_64_after_hwframe+0x76/0x7e
Freed by task 2236: kasan_save_stack+0x30/0x50 kasan_save_track+0x14/0x30 kasan_save_free_info+0x3b/0x70 __kasan_slab_free+0x47/0x70 kmem_cache_free+0x11c/0x590 __sk_destruct+0x432/0x6e0 unix_release_sock+0x9b3/0xf60 unix_release+0x8a/0xf0 __sock_release+0xb0/0x270 sock_close+0x18/0x20 __fput+0x36e/0xac0 fput_close_sync+0xe5/0x1a0 __x64_sys_close+0x7d/0xd0 do_syscall_64+0xf7/0x5e0 entry_SYSCALL_64_after_hwframe+0x76/0x7e
{
"affected": [],
"aliases": [
"CVE-2026-53033"
],
"database_specific": {
"cwe_ids": [
"CWE-825"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-06-24T17:17:14Z",
"severity": "HIGH"
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf, sockmap: Take state lock for af_unix iter\n\nWhen a BPF iterator program updates a sockmap, there is a race condition in\nunix_stream_bpf_update_proto() where the `peer` pointer can become stale[1]\nduring a state transition TCP_ESTABLISHED -\u003e TCP_CLOSE.\n\n CPU0 bpf CPU1 close\n -------- ----------\n// unix_stream_bpf_update_proto()\nsk_pair = unix_peer(sk)\nif (unlikely(!sk_pair))\n return -EINVAL;\n // unix_release_sock()\n skpair = unix_peer(sk);\n unix_peer(sk) = NULL;\n sock_put(skpair)\nsock_hold(sk_pair) // UaF\n\nMore practically, this fix guarantees that the iterator program is\nconsistently provided with a unix socket that remains stable during\niterator execution.\n\n[1]:\nBUG: KASAN: slab-use-after-free in unix_stream_bpf_update_proto+0x155/0x490\nWrite of size 4 at addr ffff8881178c9a00 by task test_progs/2231\nCall Trace:\n dump_stack_lvl+0x5d/0x80\n print_report+0x170/0x4f3\n kasan_report+0xe4/0x1c0\n kasan_check_range+0x125/0x200\n unix_stream_bpf_update_proto+0x155/0x490\n sock_map_link+0x71c/0xec0\n sock_map_update_common+0xbc/0x600\n sock_map_update_elem+0x19a/0x1f0\n bpf_prog_bbbf56096cdd4f01_selective_dump_unix+0x20c/0x217\n bpf_iter_run_prog+0x21e/0xae0\n bpf_iter_unix_seq_show+0x1e0/0x2a0\n bpf_seq_read+0x42c/0x10d0\n vfs_read+0x171/0xb20\n ksys_read+0xff/0x200\n do_syscall_64+0xf7/0x5e0\n entry_SYSCALL_64_after_hwframe+0x76/0x7e\n\nAllocated by task 2236:\n kasan_save_stack+0x30/0x50\n kasan_save_track+0x14/0x30\n __kasan_slab_alloc+0x63/0x80\n kmem_cache_alloc_noprof+0x1d5/0x680\n sk_prot_alloc+0x59/0x210\n sk_alloc+0x34/0x470\n unix_create1+0x86/0x8a0\n unix_stream_connect+0x318/0x15b0\n __sys_connect+0xfd/0x130\n __x64_sys_connect+0x72/0xd0\n do_syscall_64+0xf7/0x5e0\n entry_SYSCALL_64_after_hwframe+0x76/0x7e\n\nFreed by task 2236:\n kasan_save_stack+0x30/0x50\n kasan_save_track+0x14/0x30\n kasan_save_free_info+0x3b/0x70\n __kasan_slab_free+0x47/0x70\n kmem_cache_free+0x11c/0x590\n __sk_destruct+0x432/0x6e0\n unix_release_sock+0x9b3/0xf60\n unix_release+0x8a/0xf0\n __sock_release+0xb0/0x270\n sock_close+0x18/0x20\n __fput+0x36e/0xac0\n fput_close_sync+0xe5/0x1a0\n __x64_sys_close+0x7d/0xd0\n do_syscall_64+0xf7/0x5e0\n entry_SYSCALL_64_after_hwframe+0x76/0x7e",
"id": "GHSA-2f72-2chx-q8p6",
"modified": "2026-06-30T03:37:13Z",
"published": "2026-06-24T18:32:44Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-53033"
},
{
"type": "WEB",
"url": "https://access.redhat.com/security/cve/CVE-2026-53033"
},
{
"type": "WEB",
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2492281"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/1a59cc6b65fd3ad9915aae5970d859109d4ce9fb"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/64c2f93fc3254d3bf5de4445fb732ee5c451edb6"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/921920c34cb591947dd30c692500795a69f1e3fa"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/98f744d204e5d6fca589cd2c44c3190a0c71697f"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/c6f4015eac2e3cbc3cb7a17539e10bbb5c2049c3"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/d0d124dbcef9318e326956137b31671407094bd4"
},
{
"type": "WEB",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-53033.json"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.