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.
Metrics
Affected Vendors & Products
References
History
Fri, 10 Apr 2026 09:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Opnsense
Opnsense core |
|
| Vendors & Products |
Opnsense
Opnsense core |
Thu, 09 Apr 2026 19:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Metrics |
ssvc
|
Thu, 09 Apr 2026 15:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| 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. | |
| Title | OPNsense has an LDAP Injection via Unsanitized Username in Authentication | |
| Weaknesses | CWE-90 | |
| References |
| |
| Metrics |
cvssV3_1
|
Status: PUBLISHED
Assigner: GitHub_M
Published: 2026-04-09T14:34:20.158Z
Updated: 2026-04-09T17:45:23.099Z
Reserved: 2026-03-30T16:56:30.998Z
Link: CVE-2026-34578
Updated: 2026-04-09T17:45:11.030Z
Status : Received
Published: 2026-04-09T15:16:10.777
Modified: 2026-04-09T18:16:59.307
Link: CVE-2026-34578
No data.