# CVE-2026-99086: dm-integrity: validate the superblock on resume


- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Fix available:** Yes
- **Published:** 23 Oct 2026
- **Updated:** 23 Oct 2026
- **Also known as:** BELL-CVE-2026-99086, DEBIAN-CVE-2026-99086, GHSA-ppgf-6cf3-2qjr, UBUNTU-CVE-2026-99086

## What is CVE-2026-99086?

CVE-2026-99086 is a vulnerability in Linux, published on 23 Oct 2026. 

### Official description

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

dm-integrity: validate the superblock on resume

dm_integrity_resume() re-reads the superblock from the device so that it
picks up the flags and the recalculate position. It performs no
validation on the result, while the constructor validates the superblock
it reads and sizes all the in-memory structures according to it. The user
may modify the superblock on the underlying device while the dm-integrity
device is suspended, so that the two no longer agree.

In particular, access_journal_data() shifts the journal entry index by
ic->sb->log2_sectors_per_block, while ic->journal_section_sectors and the
journal page list were computed with the value that was present at
constructor time. Increasing log2_sectors_per_block makes the index run
past the end of the journal, and dm-integrity then writes 512 bytes
through lowmem_page_address(NULL).

Snapshot the validated superblock in the constructor and refuse to resume
if any of the fields that describe the on-disk geometry changed.

## Which versions are affected by CVE-2026-99086?


## How do I fix CVE-2026-99086?

Upgrade to a fixed version.

## Is CVE-2026-99086 being exploited?

There is no known exploitation of CVE-2026-99086 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-99086 and fix it if it is affected.

What it is: CVE-2026-99086 is a vulnerability in Linux, published on 23 Oct 2026. 
Exploitation: There is no known exploitation of CVE-2026-99086 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-2026-99086/ (Markdown: https://insights.sbomify.com/CVE-2026-99086/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-99086
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-99086
- OSV: https://osv.dev/vulnerability/CVE-2026-99086

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-99086/
Summaries are generated and may contain mistakes; the official description above is the record.