# CVE-2025-40319: bpf: Sync pending IRQ work before freeing ring buffer

> A race condition in the Linux kernel BPF ring buffer allows attackers to trigger a use-after-free, potentially leading to code execution or privilege escalation.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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:** 8 Dec 2025
- **Updated:** 15 Oct 2026
- **Also known as:** BELL-CVE-2025-40319, DEBIAN-CVE-2025-40319, GHSA-7wgc-5744-4jc8, ROOT-OS-DEBIAN-12-CVE-2025-40319, ROOT-OS-DEBIAN-13-CVE-2025-40319, ROOT-OS-UBUNTU-2204-CVE-2025-40319, ROOT-OS-UBUNTU-2404-CVE-2025-40319, UBUNTU-CVE-2025-40319

## What is CVE-2025-40319?

CVE-2025-40319 is a high-severity use after free vulnerability in Linux, published on 8 Dec 2025. 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:

bpf: Sync pending IRQ work before freeing ring buffer

Fix a race where irq_work can be queued in bpf_ringbuf_commit()
but the ring buffer is freed before the work executes.
In the syzbot reproducer, a BPF program attached to sched_switch
triggers bpf_ringbuf_commit(), queuing an irq_work. If the ring buffer
is freed before this work executes, the irq_work thread may accesses
freed memory.
Calling `irq_work_sync(&rb->work)` ensures that all pending irq_work
complete before freeing the buffer.

## Which versions are affected by CVE-2025-40319?


## How do I fix CVE-2025-40319?

Apply the vendor's patch.

## Is CVE-2025-40319 being exploited?

There is no known exploitation of CVE-2025-40319 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-40319 and fix it if it is affected.

What it is: CVE-2025-40319 is a high-severity use after free vulnerability in Linux, published on 8 Dec 2025. 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-2025-40319 in the wild and no public exploit code.

Affected product: Linux. 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-2025-40319/ (Markdown: https://insights.sbomify.com/CVE-2025-40319/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-40319
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-40319
- OSV: https://osv.dev/vulnerability/CVE-2025-40319

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-40319/
Summaries are generated and may contain mistakes; the official description above is the record.