Improper authentication in Cisco IOS XE - CVE-2025-20160
Published: September 24, 2025
Vulnerability identifier: #VU116080
CSH Severity: Medium
CVSS v4: 6.3 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N]
CVE-ID: CVE-2025-20160
CWE-ID: CWE-287
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to bypass authentication process.
The vulnerability exists due to an error in the implementation of the TACACS+ protocol where the system does not properly check whether the required TACACS+ shared secret was configured. A remote machine-in-the-middle attacker can read unencrypted TACACS+ messages or impersonate the TACACS+ server and falsely accept arbitrary authentication requests, leading to information disclosure.
Affected software
Cisco IOS XE
How to mitigate CVE-2025-20160
Install updates from vendor's website.
Cisco IOS XE - addressed in versions 17.12.6, 17.15.4