Bug ID 900789: Alert before Brute Force Protection (BFP) hash are fully utilized

Last Modified: Sep 13, 2023

Affected Product(s):
BIG-IP ASM(all modules)

Known Affected Versions:
14.1.0,,,,,, 14.1.2,,,,,,, 15.0.0, 15.0.1,,,, 15.1.0,,,,, 16.0.0,

Fixed In:
16.1.0, 16.0.1,,,,

Opened: Apr 17, 2020

Severity: 3-Major


Brute Force Protection (BFP) uses a hash table to store counters of failed logins per IP addresses and usernames. There is a separate hash table for each virtual server. When the hash table is fully utilized and new entries need to be added, the LRU entry is being removed without logging a warning.


No alert is sent when entries are evicted.


This can be encountered when Brute Force Protection is enabled and the hash table reaches its maximum capacity.



Fix Information

Alert/Warning is now announced in ASM logs, describing the status of the hash table.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips