# CVE-2025-14821: Libssh: libssh: insecure default configuration leads to local man-in-the-middle attacks on windows

> Insecure default configuration in libssh on Windows allows local attackers to perform man-in-the-middle attacks and downgrade SSH security.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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:** 7 Apr 2026
- **Updated:** 31 Aug 2026
- **Also known as:** GHSA-5jf9-8f86-jhvw, JLSEC-2026-778, MINI-63m5-4cqc-23mv, MINI-qrq6-vxgq-w6gq

## What is CVE-2025-14821?

CVE-2025-14821 is a high-severity vulnerability in Redhat Hardened Images, published on 7 Apr 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A flaw was found in libssh. This vulnerability allows local man-in-the-middle attacks, security downgrades of SSH (Secure Shell) connections, and manipulation of trusted host information, posing a significant risk to the confidentiality, integrity, and availability of SSH communications via an insecure default configuration on Windows systems where the library automatically loads configuration files from the C:\etc directory, which can be created and modified by unprivileged local users.

Weakness: CWE-427 (Uncontrolled Search Path Element)

## Which versions are affected by CVE-2025-14821?

It affects 2 products.


Products: Libssh Libssh, Redhat Hardened Images.

## How do I fix CVE-2025-14821?

Apply the vendor's patch.

## Is CVE-2025-14821 being exploited?

There is no known exploitation of CVE-2025-14821 in the wild and no public exploit code.

## Other vulnerabilities in Redhat Hardened Images

- [CVE-2026-59851](https://insights.sbomify.com/CVE-2026-59851/): Libssh: libssh: authentication bypass via missing gssapi principal check (high 8.8)
- [CVE-2025-5987](https://insights.sbomify.com/CVE-2025-5987/): Libssh: invalid return code for chacha20 poly1305 with openssl backend (high 8.1)
- [CVE-2012-4560](https://insights.sbomify.com/CVE-2012-4560/): Memory corruption in n/a (high 7.5)
- [CVE-2012-4562](https://insights.sbomify.com/CVE-2012-4562/): Integer overflow in n/a (high 7.5)
- [CVE-2012-6063](https://insights.sbomify.com/CVE-2012-6063/): Use after free in n/a (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-14821 and fix it if it is affected.

What it is: CVE-2025-14821 is a high-severity vulnerability in Redhat Hardened Images, published on 7 Apr 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-2025-14821 in the wild and no public exploit code.

Affected product: Redhat Hardened Images. 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-2025-14821/ (Markdown: https://insights.sbomify.com/CVE-2025-14821/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-14821
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-14821
- OSV: https://osv.dev/vulnerability/CVE-2025-14821

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-14821/
Summaries are generated and may contain mistakes; the official description above is the record.