7.8

CVE-2026-53033

bpf, sockmap: Take state lock for af_unix iter

In 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
Daten sind bereitgestellt durch National Vulnerability Database (NVD)
Linux ≫ Linux Kernel Version >= 5.15 < 6.1.175
Linux ≫ Linux Kernel Version >= 6.2 < 6.6.141
Linux ≫ Linux Kernel Version >= 6.7 < 6.12.91
Linux ≫ Linux Kernel Version >= 6.13 < 6.18.33
Linux ≫ Linux Kernel Version >= 6.19 < 7.0.10
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Zu dieser CVE wurde keine Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 0.14% 0.033
CVSS Metriken
Quelle Base Score Exploit Score Impact Score Vector String
416baaa9-dc9f-4396-8d5f-8c081fb06d67 7.8 1.8 5.9
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
0b0ca135-0b70-47e7-9f44-1890c2a1c46c 6.4 0.5 5.9
CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H
CWE-416 Use After Free

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.

CWE-825 Expired Pointer Dereference

The product dereferences a pointer that contains a location for memory that was previously valid, but is no longer valid.

https://git.kernel.org/stable/c/c6f4015eac2e3cbc3cb7a17539e10bbb5c2049c3
Patch
https://git.kernel.org/stable/c/d0d124dbcef9318e326956137b31671407094bd4
Patch
https://git.kernel.org/stable/c/1a59cc6b65fd3ad9915aae5970d859109d4ce9fb
Patch
https://git.kernel.org/stable/c/921920c34cb591947dd30c692500795a69f1e3fa
Patch
https://git.kernel.org/stable/c/98f744d204e5d6fca589cd2c44c3190a0c71697f
Patch
https://git.kernel.org/stable/c/64c2f93fc3254d3bf5de4445fb732ee5c451edb6
Patch
https://bugzilla.redhat.com/show_bug.cgi?id=2492281
Third Party Advisory
Issue Tracking
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-53033.json
Third Party Advisory
https://access.redhat.com/security/cve/CVE-2026-53033
Third Party Advisory