# CVE-2026-23007: block: zero non-PI portion of auto integrity buffer

> Uninitialized memory in the Linux kernel block layer integrity buffer may leak sensitive data to userspace or physical attackers.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 25 Jan 2026
- **Updated:** 21 Oct 2026
- **Also known as:** BELL-CVE-2026-23007, DEBIAN-CVE-2026-23007, GHSA-2mvm-xgm9-r324, ROOT-OS-DEBIAN-13-CVE-2026-23007, UBUNTU-CVE-2026-23007

## What is CVE-2026-23007?

CVE-2026-23007 is a medium-severity vulnerability in Linux kernel, published on 25 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:

block: zero non-PI portion of auto integrity buffer

The auto-generated integrity buffer for writes needs to be fully
initialized before being passed to the underlying block device,
otherwise the uninitialized memory can be read back by userspace or
anyone with physical access to the storage device. If protection
information is generated, that portion of the integrity buffer is
already initialized. The integrity data is also zeroed if PI generation
is disabled via sysfs or the PI tuple size is 0. However, this misses
the case where PI is generated and the PI tuple size is nonzero, but the
metadata size is larger than the PI tuple. In this case, the remainder
("opaque") of the metadata is left uninitialized.
Generalize the BLK_INTEGRITY_CSUM_NONE check to cover any case when the
metadata is larger than just the PI tuple.

Weakness: CWE-908 (Use of Uninitialized Resource)

## Which versions are affected by CVE-2026-23007?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-23007?

Apply the vendor's patch.

## Is CVE-2026-23007 being exploited?

There is no known exploitation of CVE-2026-23007 in the wild and no public exploit code.

Public exploit code:

- https://github.com/George0Papasotiriou/CVE-2026-23007-Serverless-Cold-Start-Memory-Remanence-Data-Leakage- (github_poc): https://github.com/George0Papasotiriou/CVE-2026-23007-Serverless-Cold-Start-Memory-Remanence-Data-Leakage-

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-23007 and fix it if it is affected.

What it is: CVE-2026-23007 is a medium-severity vulnerability in Linux kernel, published on 25 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-2026-23007 in the wild and no public exploit code.

Affected product: Linux kernel. 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-2026-23007/ (Markdown: https://insights.sbomify.com/CVE-2026-23007/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-23007
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-23007
- OSV: https://osv.dev/vulnerability/CVE-2026-23007

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-23007/
Summaries are generated and may contain mistakes; the official description above is the record.