CVE-2026-34578

Published Apr 9, 2026

Last updated a month ago

Overview

Description
OPNsense is a FreeBSD based firewall and routing platform. Prior to 26.1.6, OPNsense's LDAP authentication connector passes the login username directly into an LDAP search filter without calling ldap_escape(). An unauthenticated attacker can inject LDAP filter metacharacters into the username field of the WebGUI login page to enumerate valid LDAP usernames in the configured directory. When the LDAP server configuration includes an Extended Query to restrict login to members of a specific group, the same injection can be used to bypass that group membership restriction and authenticate as any LDAP user whose password is known, regardless of group membership. This vulnerability is fixed in 26.1.6.
Source
security-advisories@github.com
NVD status
Analyzed
Products
opnsense

Risk scores

CVSS 3.1

Type
Secondary
Base score
8.2
Impact score
4.2
Exploitability score
3.9
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N
Severity
HIGH

Weaknesses

security-advisories@github.com
CWE-90

Social media

Hype score
Not currently trending

Configurations