# CVE-2025-68770: bnxt_en: Fix XDP_TX path

> A race condition in the bnxt_en driver's XDP_TX path can cause packet drops and RX ring exhaustion, leading to denial of service.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 13 Jan 2026
- **Updated:** 19 Oct 2026
- **Also known as:** BELL-CVE-2025-68770, DEBIAN-CVE-2025-68770, GHSA-j6rg-wxjc-pxj8, ROOT-OS-DEBIAN-13-CVE-2025-68770, ROOT-OS-UBUNTU-2404-CVE-2025-68770, UBUNTU-CVE-2025-68770

## What is CVE-2025-68770?

CVE-2025-68770 is a high-severity vulnerability in Linux, published on 13 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

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

bnxt_en: Fix XDP_TX path

For XDP_TX action in bnxt_rx_xdp(), clearing of the event flags is not
correct.  __bnxt_poll_work() -> bnxt_rx_pkt() -> bnxt_rx_xdp() may be
looping within NAPI and some event flags may be set in earlier
iterations.  In particular, if BNXT_TX_EVENT is set earlier indicating
some XDP_TX packets are ready and pending, it will be cleared if it is
XDP_TX action again.  Normally, we will set BNXT_TX_EVENT again when we
successfully call __bnxt_xmit_xdp().  But if the TX ring has no more
room, the flag will not be set.  This will cause the TX producer to be
ahead but the driver will not hit the TX doorbell.

For multi-buf XDP_TX, there is no need to clear the event flags and set
BNXT_AGG_EVENT.  The BNXT_AGG_EVENT flag should have been set earlier in
bnxt_rx_pkt().

The visible symptom of this is that the RX ring associated with the
TX XDP ring will eventually become empty and all packets will be dropped.
Because this condition will cause the driver to not refill the RX ring
seeing that the TX ring has forever pending XDP_TX packets.

The fix is to only clear BNXT_RX_EVENT when we have successfully
called __bnxt_xmit_xdp().

Weakness: CWE-667 (Improper Locking)

## Which versions are affected by CVE-2025-68770?


## How do I fix CVE-2025-68770?

Apply the vendor's patch.

## Is CVE-2025-68770 being exploited?

There is no known exploitation of CVE-2025-68770 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-68770 and fix it if it is affected.

What it is: CVE-2025-68770 is a high-severity vulnerability in Linux, published on 13 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-68770 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-2025-68770/ (Markdown: https://insights.sbomify.com/CVE-2025-68770/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-68770
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-68770
- OSV: https://osv.dev/vulnerability/CVE-2025-68770

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-68770/
Summaries are generated and may contain mistakes; the official description above is the record.