This article provides an analysis of the situation as of early 2026. For the most up-to-date information, please refer to the Cisco Security Advisory listed above. If you'd like, I can:
To remediate an alert flagged with this string, it is critical to break down what a security scanner is detecting:
– Please verify the exact CVE ID or advisory (e.g., from Cisco PSIRT, NVD). "ssh20cisco125" does not match any known Cisco vulnerability ID. You may mean something like CVE-2018-15473 (OpenSSH user enumeration) or a Cisco-specific SSH issue.
If the target system possesses a valid username alongside its corresponding authorized public key array, this vulnerability may allow malicious entities to log into administrative accounts without verifying ownership of the matching private key. C. Resource Exhaustion & State Tracking Inconsistencies ssh20cisco125 vulnerability
While there is no single official vulnerability titled exactly "ssh20cisco125," that string typically refers to a specific SSH banner SSH-2.0-Cisco-1.25
If you have not patched your Cisco IOS XE devices recently, you must take action immediately.
Unless absolutely necessary, you should never allow the web management interface to be accessible from the public internet (WAN). This article provides an analysis of the situation
Search examples (internal use):
Legacy software versions should be inventoried immediately. You can check the current running version and active SSH configuration by executing the following commands in the Cisco privileged EXEC mode: Router# show version Router# show ip ssh Use code with caution.
Both vulnerabilities were rated with a CVSS v2 base score of , primarily due to the ease of exploitation and the severe impact on availability. The attack vector was network-based , requiring no authentication, and the complexity was considered medium because specific conditions had to be met for the reload to occur (e.g., TACACS+ configuration). "ssh20cisco125" does not match any known Cisco vulnerability
When automated tools trigger alerts around Cisco SSH 2.0 configurations, they typically map to a few notorious classes of vulnerabilities: 1. Software-Specific RCE and Privilege Escalation
To help pinpoint the exact fix, could you share the or OS version (such as IOS XE or NX-OS) experiencing this alert? If this was generated by a specific tool like Nessus or Qualys , providing the Plugin ID will allow me to track down the precise CVE mapping for you.
: Other variants require valid user credentials but allow authenticated users with restricted access to crash the platform or execute system-level commands beyond their privilege level. Potential Impact on Infrastructure
Review the output to ensure that the device is running a modern, actively supported version of Cisco IOS, IOS XE, or NX-OS. If the device returns a legacy version or shows an unpatched software train, proceed with an immediate operating system upgrade using the Cisco Software Central platform. Step 2: Implement Hardened Access Control Lists (ACLs)
The direct impact of the banner itself is to Medium severity. It does not allow an attacker to bypass authentication or execute code directly. However, it serves as a critical reconnaissance tool: