# CVE-2026-72130: nvmet-auth: reject short AUTH_RECEIVE buffers

> Remote NVMe-oF initiators can trigger heap out-of-bounds writes in Linux kernel NVMe targets when DH-HMAC-CHAP authentication is enabled.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 15 Aug 2026
- **Updated:** 21 Oct 2026
- **Also known as:** BELL-CVE-2026-72130, DEBIAN-CVE-2026-72130, GHSA-m9xx-q2g4-96mr, UBUNTU-CVE-2026-72130

## What is CVE-2026-72130?

CVE-2026-72130 is a critical memory corruption vulnerability in Linux, published on 15 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

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

nvmet-auth: reject short AUTH_RECEIVE buffers

nvmet_execute_auth_receive() trusts the AUTH_RECEIVE allocation length
after checking only that it is nonzero and matches the transfer length.
In the SUCCESS1 and FAILURE1/default states, that lets a remote NVMe-oF
initiator reach the fixed-size DH-HMAC-CHAP response builders with a
kmalloc() buffer shorter than the response, so nvmet_auth_success1() and
nvmet_auth_failure1() write past the allocation; both only WARN_ON the
short length and then format the message anyway.

Impact: A remote NVMe-oF initiator with access to an auth-enabled target
can trigger a 16-byte heap out-of-bounds write via a one-byte
AUTH_RECEIVE allocation length.

Compute the minimum response length for the current DH-HMAC-CHAP step in
nvmet_auth_receive_data_len() and report a zero data length when the
host-supplied allocation length is shorter, so the existing zero-length
check in nvmet_execute_auth_receive() rejects the command before any
builder runs. The SUCCESS1 minimum is sizeof(struct
nvmf_auth_dhchap_success1_data) plus the HMAC hash length, because the
response hash is written into the rval[] flexible-array tail, so the
minimum is state dependent rather than a flat sizeof. CHALLENGE keeps its
existing variable-length guard in nvmet_auth_challenge().

This is reachable only when in-band DH-HMAC-CHAP authentication is
configured on the target.

## Which versions are affected by CVE-2026-72130?


## How do I fix CVE-2026-72130?

Apply the vendor's patch.

## Is CVE-2026-72130 being exploited?

There is no known exploitation of CVE-2026-72130 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-72130 and fix it if it is affected.

What it is: CVE-2026-72130 is a critical memory corruption vulnerability in Linux, published on 15 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-72130 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-2026-72130/ (Markdown: https://insights.sbomify.com/CVE-2026-72130/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-72130
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-72130
- OSV: https://osv.dev/vulnerability/CVE-2026-72130

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-72130/
Summaries are generated and may contain mistakes; the official description above is the record.