Last Modified: Jun 11, 2026
Affected Product(s):
BIG-IP TMOS
Known Affected Versions:
17.1.0, 17.1.0.1, 17.1.0.2, 17.1.0.3, 17.1.1, 17.1.1.1, 17.1.1.2, 17.1.1.3, 17.1.1.4, 17.1.2, 17.1.2.1, 17.1.2.2, 17.1.3, 17.1.3.1, 17.1.3.2, 17.5.0, 17.5.1, 17.5.1.2, 17.5.1.3, 17.5.1.4, 17.5.1.5, 17.5.1.6, 21.0.0, 21.0.0.1
Opened: Apr 27, 2026 Severity: 3-Major
The timeout logic does not function properly when a TACACS server is reachable but fails to return an authentication response, resulting in a hang instead of moving to the next available server for authentication.
When the TACACS server is reachable but does not return an authentication response, the load balancer fails to move to the next TACACS server and remains stuck while attempting to authenticate the user.
Set up two TACACS servers and configure them on the BIG-IP system.
N/A
None