# CVE-2026-56624: Apache MINA SSHD: SSH certificate options lack validations

> Attackers can bypass SSH certificate restrictions to execute unauthorized commands in applications using Apache MINA SSHD.

- **Severity:** High 7.3 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 20 Jul 2026
- **Updated:** 23 Jul 2026
- **Also known as:** CLEANSTART-2026-BQ51036, CLEANSTART-2026-JH16561, CLEANSTART-2026-NF19276, DEBIAN-CVE-2026-56624, GHSA-j262-jh5j-p4fw, UBUNTU-CVE-2026-56624

## What is CVE-2026-56624?

CVE-2026-56624 is a high-severity vulnerability in Apache MINA SSHD, published on 20 Jul 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### Official description

Improper certificate validation in Apache MINA SSHD (server-side). Apache MINA SSHD is a Java library for client-side and server-side SSH.

Server-side OpenSSH user certificate validation during user authentication in an Apache MINA SSHD server did not check for the unsupported force-command or verify-required options that could be embedded in the certificate, nor did it validate these options. As a result it was possible that a user could authenticate with such a certificate that included a force-command option but still was able to execute other commands. What other command exactly would be available to the user depends on the implementation of the server.

This issue is fixed in Apache MINA SSHD 2.19.0 and 3.0.0-M5. Applications are advised to upgrade to these versions.

The fix rejects OpenSSH user certificates that include these options, since Apache MINA SSHD implements neither force-command nor sk-*-cert-v01@openssh.com user certificates (which are the only ones for which verify-required would make sense).

Weakness: CWE-295 (Improper Certificate Validation)

## Which versions are affected by CVE-2026-56624?

It affects 1 product.


Products: Apache Mina Sshd.

## How do I fix CVE-2026-56624?

Upgrade to a fixed version.

## Is CVE-2026-56624 being exploited?

There is no known exploitation of CVE-2026-56624 in the wild and no public exploit code.

## Other vulnerabilities in Apache MINA SSHD

- [CVE-2026-56452](https://insights.sbomify.com/CVE-2026-56452/): Apache MINA SSHD: Path traversal in SCP file reception (high 7.5)
- [CVE-2026-56623](https://insights.sbomify.com/CVE-2026-56623/): Apache MINA SSHD: Path traversal in org.apache.sshd:sshd-git on Windows (high 7.1)
- [CVE-2026-48827](https://insights.sbomify.com/CVE-2026-48827/): Apache MINA SSHD: Path traversal in org.apache.sshd:sshd-git (high 7.1)
- [CVE-2024-41909](https://insights.sbomify.com/CVE-2024-41909/): Apache MINA SSHD: integrity check bypass (medium 5.9)
- [CVE-2019-6111](https://insights.sbomify.com/CVE-2019-6111/): Path traversal in n/a (medium 5.9)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-56624 and fix it if it is affected.

What it is: CVE-2026-56624 is a high-severity vulnerability in Apache MINA SSHD, published on 20 Jul 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-56624 in the wild and no public exploit code.

Affected product: Apache MINA SSHD. 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-2026-56624/ (Markdown: https://insights.sbomify.com/CVE-2026-56624/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-56624
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-56624
- OSV: https://osv.dev/vulnerability/CVE-2026-56624

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From sbomify Insights: https://insights.sbomify.com/CVE-2026-56624/
Summaries are generated and may contain mistakes; the official description above is the record.