Detections
Analytics
Cisco IOS Software TACACS+ Authentication Bypass (cisco-sa-ios-tacacs-hdB7thJw)
high Nessus Plugin ID 325433
Synopsis
The remote device is missing a vendor-supplied security patchDescription
According to its self-reported version, Cisco IOS is affected by a vulnerability.- A vulnerability in the implementation of the TACACS+ protocol in Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to view sensitive data or bypass authentication.
This vulnerability exists because the system does not properly check whether the required TACACS+ shared secret is configured. A machine-in-the-middle attacker could exploit this vulnerability by intercepting and reading unencrypted TACACS+ messages or impersonating the TACACS+ server and falsely accepting arbitrary authentication requests. A successful exploit could allow the attacker to view sensitive information in a TACACS+ message or bypass authentication and gain access to the affected device.
(CVE-2025-20160)
Please see the included Cisco BIDs and Cisco Security Advisory for more information.
Solution
Upgrade to the relevant fixed version referenced in Cisco bug ID CSCwm99306See Also
https://bst.cloudapps.cisco.com/bugsearch/bug/CSCwm99306
Plugin Details
Severity: High
ID: 325433
File Name: cisco-sa-ios-tacacs-hdB7thJw-ios.nasl
Version: 1.1
Type: Combined
Family: CISCO
Published: 7/7/2026
Updated: 7/7/2026
Configuration: Enable paranoid mode
Supported Sensors: Nessus
Risk Information
VPR
Risk Factor: Medium
Score: 4.9
Percentile: 57.49
CVSS v2
Risk Factor: High
Base Score: 7.6
Temporal Score: 5.6
Vector: CVSS2#AV:N/AC:H/Au:N/C:C/I:C/A:C
CVSS Score Source: CVE-2025-20160
CVSS v3
Risk Factor: High
Base Score: 8.1
Temporal Score: 7.1
Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C
Vulnerability Information
CPE: cpe:/o:cisco:ios
Required KB Items: Host/Cisco/IOS/Version, Settings/ParanoidReport
Exploit Ease: No known exploits are available
Patch Publication Date: 9/24/2025
Vulnerability Publication Date: 9/24/2025
Reference Information
CVE: CVE-2025-20160