# Anti-Malware Security and Brute-Force Firewall <= 4.23.90 - Unauthenticated IP Address Spoofing to Brute-Force Protection and Firewall Bypass

- **ID:** WPSEC-2026-1632
- **Plugin:** Anti-Malware Security and Brute-Force Firewall (`gotmls`), https://wordpress.org/plugins/gotmls/
- **Affected versions:** all versions before 4.23.91
- **Fixed in:** 4.23.91 (Update to 4.23.91 or later.)
- **Severity:** Medium 5.3 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N)
- **Weakness:** CWE-348
- **Usage among sites WPSec scans:** plugin Low, affected versions Low (as of 2026-10-25)
- **Attack surface analysis:** https://attacksurface.wpsec.com/plugin/gotmls
- **Fix released:** 2026-10-24
- **Published:** 2026-10-25
- **URL:** https://wpsec.com/vuln/WPSEC-2026-1632/

## Description

The Anti-Malware Security and Brute-Force Firewall plugin for WordPress is vulnerable to IP Address Spoofing in all versions up to, and including, 4.23.90 due to the client IP address being taken from the CF-Connecting-IP and X-Forwarded-For headers without checking whether the request came from a trusted proxy. This makes it possible for unauthenticated attackers to spoof their IP address and evade the plugin's brute-force login lockouts and firewall IP blocking.

## References

- https://wpsec.com/vuln/WPSEC-2026-1632/
- https://plugins.svn.wordpress.org/gotmls/tags/4.23.91/
- https://wordpress.org/plugins/gotmls/

Source: WPSec, https://wpsec.com/vuln/WPSEC-2026-1632/

License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Free to use, share and adapt, also commercially, if you credit WPSec and link to this advisory.