Ssh20cisco125 Vulnerability Exclusive [patched] Jun 2026
Given the recurring nature of SSH vulnerabilities across Cisco platforms, organizations should establish a for all network infrastructure. Cisco’s security advisories are typically bundled in semiannual releases (March and September), but critical and high‑severity issues may be disclosed out of band.
The "ssh20cisco125" vulnerability, also formally identified as CVE-2023-20186 , is a specific security flaw affecting the SSH implementation in various Cisco devices. Vulnerability Name: SSH20Cisco125 CVE Identifier: CVE-2023-20186
The exclusivity of the SSH-20 vulnerability lies in its specificity to Cisco IOS and IOS XE software. Unlike some vulnerabilities that affect a broad range of devices and software, the SSH-20 vulnerability is unique to Cisco devices. This specificity means that organizations with Cisco infrastructure need to be particularly vigilant about patching and mitigating this vulnerability.
Cisco ISR Routers, Catalyst Switches (3k, 4k, 9k series), and Adaptive Security Appliances (ASA) configured with SSH. ssh20cisco125 vulnerability exclusive
The vulnerability stems from insufficient validation of user input during the SSH authentication phase. To exploit it, an attacker only needs a valid username and the associated public key – the private key is required. With a CVSS 3.1 base score of 5.3 (Medium) , the flaw is classified as a partial private‑key authentication bypass.
Run the following commands on your Cisco device to check for common misconfigurations: Check SSH Version: show ip ssh
Legacy SSH version 1 is fundamentally broken and insecure. Restrict all device lines to SSHv2 exclusively to mitigate protocol-level downgrade attacks: Device(config)# ip ssh version 2 Use code with caution. Given the recurring nature of SSH vulnerabilities across
An attacker can trigger a device reload by continuously sending crafted SSH requests, leading to a Denial of Service (DoS).
Real exploits go further—they corrupt the heap to inject a new admin user via ssh_pubkey_auth .
The identifier "SSH20CISCO125" has circulated among security research circles to denote the specific mechanism of the static credential injection. Cisco ISR Routers, Catalyst Switches (3k, 4k, 9k
While some reports suggest newer Cisco IOS-XR and Meraki products may not be directly impacted, legacy or unpatched Cisco IOS XE devices are considered high-risk targets. Mitigation and Fixes
The SSH-2-Cisco-1.25 vulnerability, also known as CVE-2006-4948, is a buffer overflow vulnerability in the SSH-2 (Secure Shell 2) implementation on Cisco IOS devices. This vulnerability allows an attacker to execute arbitrary code or cause a denial of service (DoS) on the affected device.