Ssh20cisco125 - Vulnerability

configure terminal crypto key zeroize rsa ! WARNING: This removes all existing RSA keys – do this out-of-hours crypto key generate rsa modulus 2048 Confirm the new key:

While this string does not appear as a formal CVE (Common Vulnerabilities and Exploit Disclosure) ID like CVE-2023-20198 or CVE-2021-34770, it has emerged from dark web forums and internal penetration testing reports as a shorthand for a critical, rediscovered weakness affecting running outdated SSH version 2 (SSHv2) implementations with specific cryptographic flaws tied to modulus size 125. ssh20cisco125 vulnerability

If your Cisco devices still bear the scars of a decade-old configuration, act today: regenerate your RSA keys, upgrade your IOS, and assume breach. The math doesn’t lie – and neither will the logs of a successful attack. configure terminal crypto key zeroize rsa

% Key pair was generated at: 00:00:00 UTC Jan 1 2015 Key name: myrouter.cisco.com Storage Device: private-config Usage: General Purpose Key Key Data: Modulus Length (bits): 1000 <--- DANGER Key is not exportable. From an external Linux host: The math doesn’t lie – and neither will

nmap --script ssh2-enum-algos -p 22 <cisco-ip> Then use a tool like ssh-audit :