FortiOS VPN Auth Bypass Flaw (CVE-2026-22153) Exposes Remote Access
LDAP is commonly used as a centralized authentication backend for VPN gateways. In a typical setup, users submit credentials to the VPN service, which forwards them to the LDAP server for validation. The VPN gateway then grants or denies access based on the response it receives. CVE-2026-22153 does not rely on malformed packets or memory corruption. Instead, it stems from flawed authentication logic, where certain LDAP response states can be misinterpreted under specific configurations.