In the Linux kernel, the following vulnerability has been resolved:

bpf: prevent decl_tag from being referenced in func_proto

Syzkaller was able to hit the following issue:

------------[ cut here ]------------
WARNING: CPU: 0 PID: 3609 at kernel/bpf/btf.c:1946
btf_type_id_size+0x2d5/0x9d0 kernel/bpf/btf.c:1946
Modules linked in:
CPU: 0 PID: 3609 Comm: syz-executor361 Not tainted
6.0.0-syzkaller-02734-g0326074ff465 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 09/22/2022
RIP: 0010:btf_type_id_size+0x2d5/0x9d0 kernel/bpf/btf.c:1946
Code: ef e8 7f 8e e4 ff 41 83 ff 0b 77 28 f6 44 24 10 18 75 3f e8 6d 91
e4 ff 44 89 fe bf 0e 00 00 00 e8 20 8e e4 ff e8 5b 91 e4 ff <0f> 0b 45
31 f6 e9 98 02 00 00 41 83 ff 12 74 18 e8 46 91 e4 ff 44
RSP: 0018:ffffc90003cefb40 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 0000000000000002 RCX: 0000000000000000
RDX: ffff8880259c0000 RSI: ffffffff81968415 RDI: 0000000000000005
RBP: ffff88801270ca00 R08: 0000000000000005 R09: 000000000000000e
R10: 0000000000000011 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000011 R14: ffff888026ee6424 R15: 0000000000000011
FS: 000055555641b300(0000) GS:ffff8880b9a00000(0000)
knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000f2e258 CR3: 000000007110e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
btf_func_proto_check kernel/bpf/btf.c:4447 [inline]
btf_check_all_types kernel/bpf/btf.c:4723 [inline]
btf_parse_type_sec kernel/bpf/btf.c:4752 [inline]
btf_parse kernel/bpf/btf.c:5026 [inline]
btf_new_fd+0x1926/0x1e70 kernel/bpf/btf.c:6892
bpf_btf_load kernel/bpf/syscall.c:4324 [inline]
__sys_bpf+0xb7d/0x4cf0 kernel/bpf/syscall.c:5010
__do_sys_bpf kernel/bpf/syscall.c:5069 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5067 [inline]
__x64_sys_bpf+0x75/0xb0 kernel/bpf/syscall.c:5067
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f0fbae41c69
Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 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 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc8aeb6228 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f0fbae41c69
RDX: 0000000000000020 RSI: 0000000020000140 RDI: 0000000000000012
RBP: 00007f0fbae05e10 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007f0fbae05ea0
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
</TASK>

Looks like it tries to create a func_proto which return type is
decl_tag. For the details, see Martin's spot on analysis in [0].

0: https://lore.kernel.org/bpf/CAKH8qBuQDLva_hHxxBuZzyAcYNO4ejhovz6TQeVSk8HY-2SO6g@mail.gmail.com/T/#mea6524b3fcd6298347432226e81b1e6155efc62c

No CVSS v4.0

Attack Vector Local

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

The EPSS score is 0.00026.

Key SSVC decision points have not yet been added.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions
Linux Linux unaffected
Version Status Constraints
bd16dee66ae4de3f1726c69ac901d2b7a53b0c86 affected < e9dbb4c539d058852b76937dcd7347d3f38054f2
bd16dee66ae4de3f1726c69ac901d2b7a53b0c86 affected < ea68376c8bed5cd156900852aada20c3a0874d17
Linux Linux affected
Version Status Constraints
5.16 affected —
0 unaffected < 5.16
6.0.7 unaffected ≤ 6.0.*
6.1 unaffected ≤ *

No data.

No data.

No data.

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References
Link Providers
https://git.kernel.org/stable/c/e9dbb4c539d058852b76937dcd7347d3f38054f2 cve-icon cve-icon
https://git.kernel.org/stable/c/ea68376c8bed5cd156900852aada20c3a0874d17 cve-icon cve-icon
https://lore.kernel.org/linux-cve-announce/2025123048-CVE-2022-50862-124f@gregkh/T cve-icon
https://nvd.nist.gov/vuln/detail/CVE-2022-50862 cve-icon
https://www.cve.org/CVERecord?id=CVE-2022-50862 cve-icon
History

Thu, 01 Jan 2026 00:15:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

 cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Low

Tue, 30 Dec 2025 12:30:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: bpf: prevent decl_tag from being referenced in func_proto Syzkaller was able to hit the following issue: ------------[ cut here ]------------ WARNING: CPU: 0 PID: 3609 at kernel/bpf/btf.c:1946 btf_type_id_size+0x2d5/0x9d0 kernel/bpf/btf.c:1946 Modules linked in: CPU: 0 PID: 3609 Comm: syz-executor361 Not tainted 6.0.0-syzkaller-02734-g0326074ff465 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 RIP: 0010:btf_type_id_size+0x2d5/0x9d0 kernel/bpf/btf.c:1946 Code: ef e8 7f 8e e4 ff 41 83 ff 0b 77 28 f6 44 24 10 18 75 3f e8 6d 91 e4 ff 44 89 fe bf 0e 00 00 00 e8 20 8e e4 ff e8 5b 91 e4 ff <0f> 0b 45 31 f6 e9 98 02 00 00 41 83 ff 12 74 18 e8 46 91 e4 ff 44 RSP: 0018:ffffc90003cefb40 EFLAGS: 00010293 RAX: 0000000000000000 RBX: 0000000000000002 RCX: 0000000000000000 RDX: ffff8880259c0000 RSI: ffffffff81968415 RDI: 0000000000000005 RBP: ffff88801270ca00 R08: 0000000000000005 R09: 000000000000000e R10: 0000000000000011 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000011 R14: ffff888026ee6424 R15: 0000000000000011 FS: 000055555641b300(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000f2e258 CR3: 000000007110e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> btf_func_proto_check kernel/bpf/btf.c:4447 [inline] btf_check_all_types kernel/bpf/btf.c:4723 [inline] btf_parse_type_sec kernel/bpf/btf.c:4752 [inline] btf_parse kernel/bpf/btf.c:5026 [inline] btf_new_fd+0x1926/0x1e70 kernel/bpf/btf.c:6892 bpf_btf_load kernel/bpf/syscall.c:4324 [inline] __sys_bpf+0xb7d/0x4cf0 kernel/bpf/syscall.c:5010 __do_sys_bpf kernel/bpf/syscall.c:5069 [inline] __se_sys_bpf kernel/bpf/syscall.c:5067 [inline] __x64_sys_bpf+0x75/0xb0 kernel/bpf/syscall.c:5067 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f0fbae41c69 Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 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 c0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffc8aeb6228 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f0fbae41c69 RDX: 0000000000000020 RSI: 0000000020000140 RDI: 0000000000000012 RBP: 00007f0fbae05e10 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007f0fbae05ea0 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 </TASK> Looks like it tries to create a func_proto which return type is decl_tag. For the details, see Martin's spot on analysis in [0]. 0: https://lore.kernel.org/bpf/CAKH8qBuQDLva_hHxxBuZzyAcYNO4ejhovz6TQeVSk8HY-2SO6g@mail.gmail.com/T/#mea6524b3fcd6298347432226e81b1e6155efc62c
Title bpf: prevent decl_tag from being referenced in func_proto
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2025-12-30T12:15:35.177Z

Reserved: 2025-12-30T12:06:07.135Z

Link: CVE-2022-50862

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Awaiting Analysis

Published: 2025-12-30T13:16:00.997

Modified: 2025-12-31T20:43:05.160

Link: CVE-2022-50862

cve-icon Redhat

Severity : Low

Publid Date: 2025-12-30T00:00:00Z

Links: CVE-2022-50862 - Bugzilla

cve-icon OpenCVE Enrichment

No data.

Weaknesses

No weakness.