# CVE-2025-71125: tracing: Do not register unsupported perf events

> A null pointer dereference in the Linux kernel tracing subsystem can cause a system crash when registering unsupported perf events.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 14 Jan 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-74610, BELL-CVE-2025-71125, DEBIAN-CVE-2025-71125, GHSA-hxvv-8gx6-fvgh, ROOT-OS-UBUNTU-2204-CVE-2025-71125, ROOT-OS-UBUNTU-2404-CVE-2025-71125, UBUNTU-CVE-2025-71125

## What is CVE-2025-71125?

CVE-2025-71125 is a medium-severity vulnerability in Linux kernel, published on 14 Jan 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

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

tracing: Do not register unsupported perf events

Synthetic events currently do not have a function to register perf events.
This leads to calling the tracepoint register functions with a NULL
function pointer which triggers:

 ------------[ cut here ]------------
 WARNING: kernel/tracepoint.c:175 at tracepoint_add_func+0x357/0x370, CPU#2: perf/2272
 Modules linked in: kvm_intel kvm irqbypass
 CPU: 2 UID: 0 PID: 2272 Comm: perf Not tainted 6.18.0-ftest-11964-ge022764176fc-dirty #323 PREEMPTLAZY
 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.17.0-debian-1.17.0-1 04/01/2014
 RIP: 0010:tracepoint_add_func+0x357/0x370
 Code: 28 9c e8 4c 0b f5 ff eb 0f 4c 89 f7 48 c7 c6 80 4d 28 9c e8 ab 89 f4 ff 31 c0 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc <0f> 0b 49 c7 c6 ea ff ff ff e9 ee fe ff ff 0f 0b e9 f9 fe ff ff 0f
 RSP: 0018:ffffabc0c44d3c40 EFLAGS: 00010246
 RAX: 0000000000000001 RBX: ffff9380aa9e4060 RCX: 0000000000000000
 RDX: 000000000000000a RSI: ffffffff9e1d4a98 RDI: ffff937fcf5fd6c8
 RBP: 0000000000000001 R08: 0000000000000007 R09: ffff937fcf5fc780
 R10: 0000000000000003 R11: ffffffff9c193910 R12: 000000000000000a
 R13: ffffffff9e1e5888 R14: 0000000000000000 R15: ffffabc0c44d3c78
 FS:  00007f6202f5f340(0000) GS:ffff93819f00f000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 000055d3162281a8 CR3: 0000000106a56003 CR4: 0000000000172ef0
 Call Trace:
  <TASK>
  tracepoint_probe_register+0x5d/0x90
  synth_event_reg+0x3c/0x60
  perf_trace_event_init+0x204/0x340
  perf_trace_init+0x85/0xd0
  perf_tp_event_init+0x2e/0x50
  perf_try_init_event+0x6f/0x230
  ? perf_event_alloc+0x4bb/0xdc0
  perf_event_alloc+0x65a/0xdc0
  __se_sys_perf_event_open+0x290/0x9f0
  do_syscall_64+0x93/0x7b0
  ? entry_SYSCALL_64_after_hwframe+0x76/0x7e
  ? trace_hardirqs_off+0x53/0xc0
  entry_SYSCALL_64_after_hwframe+0x76/0x7e

Instead, have the code return -ENODEV, which doesn't warn and has perf
error out with:

 # perf record -e synthetic:futex_wait
Error:
The sys_perf_event_open() syscall returned with 19 (No such device) for event (synthetic:futex_wait).
"dmesg | grep -i perf" may provide additional information.

Ideally perf should support synthetic events, but for now just fix the
warning. The support can come later.

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2025-71125?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2025-71125?

Apply the vendor's patch.

## Is CVE-2025-71125 being exploited?

There is no known exploitation of CVE-2025-71125 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-71125 and fix it if it is affected.

What it is: CVE-2025-71125 is a medium-severity vulnerability in Linux kernel, published on 14 Jan 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-71125 in the wild and no public exploit code.

Affected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2025-71125/ (Markdown: https://insights.sbomify.com/CVE-2025-71125/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-71125
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-71125
- OSV: https://osv.dev/vulnerability/CVE-2025-71125

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-71125/
Summaries are generated and may contain mistakes; the official description above is the record.