Vulnerability · Published May 13, 2026 · Assigned by GitHub_M

CVE-2026-44195OPNsense: Authentication lockout bypass

Medium 5.3

In plain English

A medium-severity security flaw in core from opnsense. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 25% of all known vulnerabilities).

Severity (CVSS 3.1)5.3Medium

Exploit odds (30 days)0.3%top 75.1% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official 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.

Affected products (as reported)

Vendor	Product	Versions
opnsense	core	< 26.1.7

Weakness: CWE-307 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

References

https://github.com/opnsense/core/security/advisories/GHSA-h3vx-4q27-rc42 x_refsource_CONFIRM
https://gist.github.com/sopex/b9786e72e2a5d9b1bbd81ed8477c351b exploit