CVE-2026-44195

OPNsense: Authentication lockout bypass

Published May 13, 2026 CVSS 3.1 · 5.3 Medium EPSS < 1% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
First Time appeared Opnsense opnsense
CPEs cpe:2.3:a:opnsense:opnsense:*:*:*:*:*:*:*:*
Vendors & Products Opnsense opnsense
Type Values Removed Values Added
References
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Opnsense
Opnsense core
Vendors & Products Opnsense
Opnsense core
Type Values Removed Values Added
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.
Title OPNsense: Authentication lockout bypass
Weaknesses CWE-307
References
Metrics cvssV3_1

{'score': 5.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
May 14, 2026, 1:46 PM
Reserved
May 5, 2026, 3:13 PM
Status
Analyzed
Published
May 13, 2026, 10:16 PM
Modified
Oct 26, 2026, 2:10 PM