# CVE-2026-99087: dm-integrity: fix NULL pointer dereference when the 'R' flag is used


- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Fix available:** Yes
- **Published:** 23 Oct 2026
- **Updated:** 23 Oct 2026
- **Also known as:** AZL-110993, BELL-CVE-2026-99087, DEBIAN-CVE-2026-99087, GHSA-458p-v4rq-r32g, UBUNTU-CVE-2026-99087

## What is CVE-2026-99087?

CVE-2026-99087 is a vulnerability in Linux, published on 23 Oct 2026. 

### Official description

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

dm-integrity: fix NULL pointer dereference when the 'R' flag is used

If the dm-integrity device has the SB_FLAG_DIRTY_BITMAP flag set and the
user activates the device in the 'R' mode, a crash in dm_integrity_resume
happens because the function attempts to read the journal containing the
bitmap.

This patch makes dm-integrity skip any writes to the device in
dm_integrity_resume if the device is activated in the 'R' mode.

## Which versions are affected by CVE-2026-99087?


## How do I fix CVE-2026-99087?

Upgrade to a fixed version.

## Is CVE-2026-99087 being exploited?

There is no known exploitation of CVE-2026-99087 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-99087 and fix it if it is affected.

What it is: CVE-2026-99087 is a vulnerability in Linux, published on 23 Oct 2026. 
Exploitation: There is no known exploitation of CVE-2026-99087 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-2026-99087/ (Markdown: https://insights.sbomify.com/CVE-2026-99087/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-99087
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-99087
- OSV: https://osv.dev/vulnerability/CVE-2026-99087

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-99087/
Summaries are generated and may contain mistakes; the official description above is the record.