# CVE-2025-68348: block: fix memory leak in __blkdev_issue_zero_pages

> A memory leak in the Linux kernel block layer allows local attackers to cause denial of service by triggering fatal signals during zero-page operations.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 24 Dec 2025
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2025-68348, DEBIAN-CVE-2025-68348, GHSA-9hww-p592-6h89, UBUNTU-CVE-2025-68348

## What is CVE-2025-68348?

CVE-2025-68348 is a memory corruption vulnerability in Linux, published on 24 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:

block: fix memory leak in __blkdev_issue_zero_pages

Move the fatal signal check before bio_alloc() to prevent a memory
leak when BLKDEV_ZERO_KILLABLE is set and a fatal signal is pending.

Previously, the bio was allocated before checking for a fatal signal.
If a signal was pending, the code would break out of the loop without
freeing or chaining the just-allocated bio, causing a memory leak.

This matches the pattern already used in __blkdev_issue_write_zeroes()
where the signal check precedes the allocation.

## Which versions are affected by CVE-2025-68348?


## How do I fix CVE-2025-68348?

Apply the vendor's patch.

## Is CVE-2025-68348 being exploited?

There is no known exploitation of CVE-2025-68348 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-68348 and fix it if it is affected.

What it is: CVE-2025-68348 is a memory corruption vulnerability in Linux, published on 24 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-2025-68348 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-2025-68348/ (Markdown: https://insights.sbomify.com/CVE-2025-68348/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-68348
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-68348
- OSV: https://osv.dev/vulnerability/CVE-2025-68348

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-68348/
Summaries are generated and may contain mistakes; the official description above is the record.