Banhammer – Monitor Site Traffic, Block Bad Users and Bots <= 3.4.8 - Unauthenticated Protection Mechanism Bypass

2025-09-25 14:27
Jonas Benjamin Friedli

Strategic Overview

Vulnerability Overview

The Banhammer – Monitor Site Traffic, Block Bad Users and Bots plugin for WordPress is vulnerable to Blocking Bypass in all versions up to, and including, 3.4.8. This is due to a site-wide “secret key” being deterministically generated from a constant character set using md5() and base64_encode() and then stored in the `banhammer_secret_key` option. This makes it possible for unauthenticated attackers to bypass the plugin’s logging and blocking by appending a GET parameter named `banhammer-process_{SECRET}` where `{SECRET}` is the predictable value, thereby causing Banhammer to abort its protections for that request.

Technical Analysis

REMEDIATION: Update to version 3.4.9, or a newer patched version --- IDENTIFIER: CWE-330 (Use of Insufficiently Random Values) The product uses insufficiently random numbers or values in a security context that depends on unpredictable numbers.

External References

Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C