Critical RCE Vulnerability Found in OpenSSH — Patch Immediately

Security researchers have disclosed a critical remote code execution (RCE) vulnerability in OpenSSH. The flaw, tracked as CVE-2026-4193, carries a CVSS score of 9.8 and affects OpenSSH versions 8.5 through 9.6.

What Happened?

The vulnerability exists in the sshd daemon’s handling of pre-authentication requests. An unauthenticated attacker can execute arbitrary code with root privileges — without needing any login credentials.

Who Is Affected?

• OpenSSH versions 8.5p1 through 9.6p1
• Ubuntu, Debian, CentOS, Fedora, Kali Linux default packages
• Estimated 14 million internet-facing servers

How to Fix It

# Ubuntu/Debian
sudo apt update && sudo apt install --only-upgrade openssh-server
# CentOS/AlmaLinux
sudo dnf update openssh-server
# Verify
ssh -V

The SudoFlare Takeaway

Patch this immediately. Exploit code is already circulating. Restrict SSH access to specific IPs using firewall rules as an additional layer of defence. Use key-based authentication and disable root login over SSH.