Vulnerability — Ssh-2.0-cisco-1.25

The SSH-2.0-Cisco-1.25 vulnerability is a security flaw in the Secure Shell (SSH) protocol implementation on certain Cisco devices. This vulnerability can allow an attacker to gain unauthorized access to the device, potentially leading to a compromise of the system's confidentiality, integrity, and availability.

| CVE | Description | Fixed in | |------|-------------|-----------| | | SSHv2 server DoS via crafted SSH packet → reload | IOS 15.1(2)T, 15.2(1)T | | CVE-2015-6274 | Algorithm negotiation bypass → weak encryption forced | IOS 15.4(3)M, 15.5(3)M | | CVE-2016-6376 | Memory exhaustion via multiple SSHv2 key exchanges | IOS 15.5(3)M3 | | CVE-2018-0151 | Remote code execution via SSHv2 (rare, but present in older banners) | IOS 15.6(3)M2 | ssh-2.0-cisco-1.25 vulnerability

! Add an ACL to management plane (Control Plane Policing or management ACL) access-list 100 permit tcp host 192.168.1.100 any eq 22 access-list 100 deny tcp any any eq 22 line vty 0 4 access-class 100 in The SSH-2

The appearance of this string in security reports usually indicates the device is running a version of Cisco software that has not yet been hardened against recent SSH exploits. There are two primary security concerns currently associated with this banner: 1. The Terrapin Attack (CVE-2023-48795) Add an ACL to management plane (Control Plane

Why that banner matters