CVE-2025-14942 is a critical security vulnerability classified under CWE-287 (Improper Authentication) affecting the wolfSSH library, a component of the wolfSSL suite widely used for embedded SSH communications. The vulnerability arises from flaws in the key exchange state machine within wolfSSH versions 1.4.21 and earlier. An attacker can manipulate the state machine to cause the client to leak its password in plaintext, send a bogus cryptographic signature, or bypass user authentication entirely. This means that an attacker positioned as a man-in-the-middle or with network access can intercept or manipulate the SSH handshake to compromise authentication mechanisms. Although the primary impact is on client applications, server applications using wolfSSH share the same defect, posing a risk even if no active attacks have been reported against servers yet. The vulnerability requires no privileges and no user interaction, making exploitation straightforward in vulnerable environments. The CVSS 4.0 score of 9.4 reflects the high impact on confidentiality (password leakage), integrity (bogus signatures), and availability (authentication bypass). The flaw undermines the fundamental trust model of SSH connections, potentially allowing unauthorized access and credential compromise. The vulnerability was responsibly disclosed by security researchers from Valeo and Telecom SudParis. Immediate remediation involves updating wolfSSH to patched versions or applying vendor-provided fixes and rotating any credentials used during the vulnerable period.

For European organizations, the impact of CVE-2025-14942 is significant, especially for sectors relying on embedded systems, IoT devices, automotive telematics, industrial control systems, and telecom infrastructure where wolfSSH is deployed. Compromise of authentication can lead to unauthorized access to sensitive systems, data exfiltration, and potential lateral movement within networks. The leakage of client passwords in cleartext exposes credentials to interception, increasing the risk of broader compromise. Bogus signatures and authentication bypass can allow attackers to impersonate legitimate users or devices, undermining system integrity and trust. This can disrupt critical services, cause data breaches, and lead to regulatory non-compliance under GDPR due to unauthorized access to personal or sensitive data. The absence of known exploits in the wild provides a window for proactive defense, but the ease of exploitation and critical severity necessitate urgent action. Organizations using wolfSSH in client or server roles must consider the vulnerability a high priority for patching and incident prevention.

1. Immediately update all wolfSSH client and server applications to the latest patched version provided by wolfSSL that addresses CVE-2025-14942. 2. If immediate updates are not feasible, apply any available vendor patches or workarounds to mitigate the key exchange state machine flaw. 3. Rotate all credentials (passwords, keys) used by affected wolfSSH clients and servers to prevent reuse of potentially compromised secrets. 4. Conduct network monitoring for unusual SSH handshake anomalies or unexpected authentication failures that could indicate exploitation attempts. 5. Implement network segmentation and strict access controls to limit exposure of vulnerable wolfSSH endpoints. 6. Review and update incident response plans to include detection and remediation steps for wolfSSH-related authentication bypass. 7. Engage with vendors and suppliers to verify wolfSSH usage in embedded or third-party devices and ensure they are patched. 8. Consider deploying additional authentication layers such as multi-factor authentication (MFA) where possible to reduce risk from credential compromise. 9. Perform vulnerability scanning and penetration testing focused on SSH implementations to identify any residual weaknesses. 10. Maintain awareness of any emerging exploit reports or threat intelligence related to this vulnerability for timely response.