OpenSSH, the most widely used tool for remotely managing Linux and BSD systems, received patches for two vulnerabilities. One of the flaws could allow attackers to perform a man-in-the-middle attack against OpenSSH clients with a certain configuration and impersonate a server to intercept sensitive communications. While the second vulnerability can lead to CPU resource exhaustion.
“SSH sessions can be a prime target for attackers aiming to intercept credentials or hijack sessions,” researchers from Qualys who found the flaws wrote in their report. “If compromised, hackers could view or manipulate sensitive data, move across multiple critical servers laterally, and exfiltrate valuable information such as database credentials. Such breaches can lead to reputational damage, violate compliance mandates (e.g., GDPR, HIPAA, PCI-DSS), and potentially disrupt critical operations by forcing system downtime to contain the threat.”
The man-in-the-middle vulnerability, tracked as CVE-2025-26465, was introduced in the code over 10 years ago in December 2014. As such it impacts all OpenSSH versions from 6.8p1 through 9.9p1.
