SUSE Fleet SSH Auto-Trust Vulnerability Enables MitM Attack
CVE-2025-23390 Published on October 15, 2026
Fleet doesn’t validate a server’s certificate when connecting through SSH
A vulnerability has been identified within Fleet where, by default, Fleet will automatically trust a remote servers certificate when connecting through SSH if the certificate isnt set in the `known_hosts` file. This could allow the execution of a man-in-the-middle (MitM) attack against Fleet. In case the server that is being connected to has a trusted entry in the known_hosts file, then Fleet will correctly check the authenticity of the presented certificate.
Vulnerability Analysis
CVE-2025-23390 is exploitable with network access, and requires small amount of user privileges. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to be low. considered to have a small impact on confidentiality and integrity and availability.
Weakness Type
Improper Certificate Validation
The software does not validate, or incorrectly validates, a certificate. When a certificate is invalid or malicious, it might allow an attacker to spoof a trusted entity by interfering in the communication path between the host and client. The software might connect to a malicious host while believing it is a trusted host, or the software might be deceived into accepting spoofed data that appears to originate from a trusted host.
Affected Versions
SUSE fleet:- Version 0.9.0-rc.1 and below 0.10.12 is affected.
- Version 0.11.0 and below 0.11.7 is affected.
- Version 0.12.0 and below 0.12.2 is affected.