# CVE-2025-68820: ext4: xattr: fix null pointer deref in ext4_raw_inode()

> A null pointer dereference in the Linux kernel ext4 filesystem allows local attackers to cause a system crash via corrupted filesystem images.

- **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:** 13 Jan 2026
- **Updated:** 19 Oct 2026
- **Also known as:** BELL-CVE-2025-68820, DEBIAN-CVE-2025-68820, GHSA-mp4c-25vm-9w6p, ROOT-OS-UBUNTU-2204-CVE-2025-68820, ROOT-OS-UBUNTU-2404-CVE-2025-68820, UBUNTU-CVE-2025-68820

## What is CVE-2025-68820?

CVE-2025-68820 is a vulnerability in Linux, published on 13 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:

ext4: xattr: fix null pointer deref in ext4_raw_inode()

If ext4_get_inode_loc() fails (e.g. if it returns -EFSCORRUPTED),
iloc.bh will remain set to NULL. Since ext4_xattr_inode_dec_ref_all()
lacks error checking, this will lead to a null pointer dereference
in ext4_raw_inode(), called right after ext4_get_inode_loc().

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2025-68820?


## How do I fix CVE-2025-68820?

Apply the vendor's patch.

## Is CVE-2025-68820 being exploited?

There is no known exploitation of CVE-2025-68820 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-68820 and fix it if it is affected.

What it is: CVE-2025-68820 is a vulnerability in Linux, published on 13 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-2025-68820 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-2025-68820/ (Markdown: https://insights.sbomify.com/CVE-2025-68820/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-68820
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-68820
- OSV: https://osv.dev/vulnerability/CVE-2025-68820

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-68820/
Summaries are generated and may contain mistakes; the official description above is the record.