Description
OPNsense is a FreeBSD based firewall and routing platform. Prior to 26.1.7, a logic flaw in the OPNsense lockout_handler allows an unauthenticated attacker to continuously reset the authentication failure counter for their IP address. By interjecting a crafted username containing a success keyword ("Accepted" or "Successful login") between normal brute-force attempts, an attacker can prevent the failure counter from ever reaching the lockout threshold. This vulnerability is fixed in 26.1.7.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:NWeakness enumeration
Affected software
No affected versions have been published.
Timeline
- Published
- May 13, 2026
- Last modified
- Jun 17, 2026
- NVD status
- Analyzed