# CVE-2026-89770: iomap: don't free integrity payload that doesn't exist

> A local attacker can cause a kernel crash via NULL pointer dereference in iomap when integrity payload is missing.

- **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:** 11 Sep 2026
- **Updated:** 19 Oct 2026
- **Also known as:** DEBIAN-CVE-2026-89770, GHSA-p8q7-qqp3-r9v3, UBUNTU-CVE-2026-89770

## What is CVE-2026-89770?

CVE-2026-89770 is a vulnerability in Linux, published on 11 Sep 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:

iomap: don't free integrity payload that doesn't exist

fs_bio_integrity_alloc might not allocate a bio integrity payload if PI
verification is disabled on the block device.  Check for that case before
calling fs_bio_integrity_free in iomap_bio_read_folio_range_sync to
avoid a NULL pointer dereferences.

Make the branch cover the PI verification as well - while
fs_bio_integrity_verify works without an integrity payload, it requires
one to actually do useful work.

## Which versions are affected by CVE-2026-89770?


## How do I fix CVE-2026-89770?

Apply the vendor's patch.

## Is CVE-2026-89770 being exploited?

There is no known exploitation of CVE-2026-89770 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-89770 and fix it if it is affected.

What it is: CVE-2026-89770 is a vulnerability in Linux, published on 11 Sep 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-2026-89770 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-2026-89770/ (Markdown: https://insights.sbomify.com/CVE-2026-89770/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-89770
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-89770
- OSV: https://osv.dev/vulnerability/CVE-2026-89770

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-89770/
Summaries are generated and may contain mistakes; the official description above is the record.