Cloudanix VulnDB

CVE-2025-38285

Medium · 5.5

CVSS

5.5

EPSS

0.2%

Published

Jul 10, 2025

CISA due date

—

Cloudanix analysis

Next patch cycle SSVC: Track

A coding oversight in the Linux kernel's tracing tools could cause warning messages when certain monitoring programs run, but it is unlikely to be abused by attackers.

Exploitation
Local Privilege
Attacker needs
Low Privilege
Complexity
Low
Impact
Denial Of Service
Component
OS kernel
Class
Other
Remediation
Upgrade
Effort
Medium
Patch risk
Low

What it actually does

Triggers a WARN_ON_ONCE in get_bpf_raw_tp_regs when tracepoints such as trace_mmap_lock_acquire_returned cause nested BPF stack tracing calls.

Why it matters to the business

May produce kernel warnings on systems performing advanced tracing, with low operational risk given the low EPSS and lack of KEV listing; widespread kernel deployment increases exposure surface.

How an attack unfolds

An attacker loads a BPF program that exercises stackmap operations under mmap lock tracing, causing the nested call path that fires the warning; unrelated threat actor campaigns listed do not target this issue.

How to fix it

Apply the referenced kernel fix removing the WARN_ON_ONCE; for openssh/openssh-portable update to faec50b554730338c0e9f34966c11368920b6a78.

How to confirm the fix worked

Confirm absence of the warning at kernel/trace/bpf_trace.c:1861 after applying the fix and re-testing the syzkaller reproducer or equivalent mmap lock tracing workload.

Typical attack path

  1. Identify systems running affected kernel versions with BPF tracing enabled
  2. Craft or load a BPF program that triggers mmap_lock tracepoints
  3. Invoke operations that lead to nested bpf_get_stack_raw_tp calls
  4. Observe kernel warning in logs or console

How to detect it

Search kernel logs and dmesg for the exact warning string from get_bpf_raw_tp_regs; inspect BPF program loads around stackmap operations.

  • WARNING: CPU.*get_bpf_raw_tp_regs
  • kernel/trace/bpf_trace.c:1861

What your security team should do

  • Prioritize kernel updates on systems using raw tracepoint BPF programs
  • Monitor for WARN messages in dmesg related to bpf_trace.c
  • Review BPF program usage for nested tracepoint patterns

The record

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix WARN() in get_bpf_raw_tp_regs syzkaller reported an issue: WARNING: CPU: 3 PID: 5971 at kernel/trace/bpf_trace.c:1861 get_bpf_raw_tp_regs+0xa4/0x100 kernel/trace/bpf_trace.c:1861 Modules linked in: CPU: 3 UID: 0 PID: 5971 Comm: syz-executor205 Not tainted 6.15.0-rc5-syzkaller-00038-g707df3375124 #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 RIP: 0010:get_bpf_raw_tp_regs+0xa4/0x100 kernel/trace/bpf_trace.c:1861 RSP: 0018:ffffc90003636fa8 EFLAGS: 00010293 RAX: 0000000000000000 RBX: 0000000000000003 RCX: ffffffff81c6bc4c RDX: ffff888032efc880 RSI: ffffffff81c6bc83 RDI: 0000000000000005 RBP: ffff88806a730860 R08: 0000000000000005 R09: 0000000000000003 R10: 0000000000000004 R11: 0000000000000000 R12: 0000000000000004 R13: 0000000000000001 R14: ffffc90003637008 R15: 0000000000000900 FS: 0000000000000000(0000) GS:ffff8880d6cdf000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7baee09130 CR3: 0000000029f5a000 CR4: 0000000000352ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ____bpf_get_stack_raw_tp kernel/trace/bpf_trace.c:1934 [inline] bpf_get_stack_raw_tp+0x24/0x160 kernel/trace/bpf_trace.c:1931 bpf_prog_ec3b2eefa702d8d3+0x43/0x47 bpf_dispatcher_nop_func include/linux/bpf.h:1316 [inline] __bpf_prog_run include/linux/filter.h:718 [inline] bpf_prog_run include/linux/filter.h:725 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2363 [inline] bpf_trace_run3+0x23f/0x5a0 kernel/trace/bpf_trace.c:2405 __bpf_trace_mmap_lock_acquire_returned+0xfc/0x140 include/trace/events/mmap_lock.h:47 __traceiter_mmap_lock_acquire_returned+0x79/0xc0 include/trace/events/mmap_lock.h:47 __do_trace_mmap_lock_acquire_returned include/trace/events/mmap_lock.h:47 [inline] trace_mmap_lock_acquire_returned include/trace/events/mmap_lock.h:47 [inline] __mmap_lock_do_trace_acquire_returned+0x138/0x1f0 mm/mmap_lock.c:35 __mmap_lock_trace_acquire_returned include/linux/mmap_lock.h:36 [inline] mmap_read_trylock include/linux/mmap_lock.h:204 [inline] stack_map_get_build_id_offset+0x535/0x6f0 kernel/bpf/stackmap.c:157 __bpf_get_stack+0x307/0xa10 kernel/bpf/stackmap.c:483 ____bpf_get_stack kernel/bpf/stackmap.c:499 [inline] bpf_get_stack+0x32/0x40 kernel/bpf/stackmap.c:496 ____bpf_get_stack_raw_tp kernel/trace/bpf_trace.c:1941 [inline] bpf_get_stack_raw_tp+0x124/0x160 kernel/trace/bpf_trace.c:1931 bpf_prog_ec3b2eefa702d8d3+0x43/0x47 Tracepoint like trace_mmap_lock_acquire_returned may cause nested call as the corner case show above, which will be resolved with more general method in the future. As a result, WARN_ON_ONCE will be triggered. As Alexei suggested, remove the WARN_ON_ONCE first.

Affected packages

Ecosystem Package Introduced Fixed
Debian:11 linux 0 No fix
Debian:12 linux 0 No fix
Debian:13 linux 0 6.12.35-1
Debian:14 linux 0 6.12.35-1
Linux Kernel 5.2.0 5.4.295
Mageia:9 kernel 0 6.6.101-1.mga9
Mageia:9 kernel-linus 0 6.6.101-1.mga9
Mageia:9 kmod-virtualbox 0 7.1.10-7.mga9
Mageia:9 kmod-xtables-addons 0 3.24-83.mga9
Mageia:9 wireless-regdb 0 20250710-1.mga9

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