# CVE-2026-68129: gve: fix Rx queue stall on alloc failure

> An attacker can cause a permanent network queue stall in the gve driver by triggering memory allocation failures, 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:** 10 Aug 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-95010, BELL-CVE-2026-68129, DEBIAN-CVE-2026-68129, GHSA-wqfg-pmq9-xr26, UBUNTU-CVE-2026-68129

## What is CVE-2026-68129?

CVE-2026-68129 is a high-severity denial of service vulnerability in Linux, published on 10 Aug 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:

gve: fix Rx queue stall on alloc failure

When the system is under extreme memory pressure, page allocations can
fail during the Rx buffer refill loop. If the number of buffers posted
to hardware falls below a critical low threshold and the refill loop
exits due to allocation failures, the queue can stall:

1. The device drops incoming packets because there are no descriptors.
2. Since no packets are processed, no Rx completions are generated.
3. Because no completions occur, NAPI is never scheduled, preventing
   the refill loop from running again even after memory is freed.

This results in a permanent queue stall.

Resolve this by introducing a starvation recovery timer for each Rx queue.
If the number of buffers posted to hardware falls below a critical low
threshold, start a timer to periodically reschedule NAPI. Once NAPI runs
and successfully refills the queue above the threshold, the timer is
not rescheduled.

The threshold is set to 32 because a single maximum-sized Receive Segment
Coalescing (RSC) packet can consume up to 19 descriptors in the Rx path.
Lower thresholds (such as 8 or 16) would be insufficient to process a
complete maximum-sized RSC packet, risking packet drops or unexpected
hardware behavior under memory pressure. Setting the threshold to 32
guarantees a safe margin to handle at least one full RSC packet.

Weakness: CWE-400 (Uncontrolled Resource Consumption)

## Which versions are affected by CVE-2026-68129?


## How do I fix CVE-2026-68129?

Apply the vendor's patch.

## Is CVE-2026-68129 being exploited?

There is no known exploitation of CVE-2026-68129 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-68129 and fix it if it is affected.

What it is: CVE-2026-68129 is a high-severity denial of service vulnerability in Linux, published on 10 Aug 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-2026-68129 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-2026-68129/ (Markdown: https://insights.sbomify.com/CVE-2026-68129/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-68129
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-68129
- OSV: https://osv.dev/vulnerability/CVE-2026-68129

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-68129/
Summaries are generated and may contain mistakes; the official description above is the record.