GeoNetwork is a catalog application to manage spatially referenced resources. From 3.0.0 until 4.2.15 and 4.4.10, requesting a nonexistent or unauthorized service URL can cause an error page to reflect attacker-controlled request content inside an AngularJS application without adequately neutralizing it for template evaluation. A remote attacker can induce a victim, including an administrator, to open a crafted link so the reflected value is evaluated as an AngularJS template expression. Combined with known AngularJS sandbox-escape techniques, this can execute arbitrary JavaScript in the victim's authenticated browser session, disclose information, or perform actions as the victim. This issue is fixed in versions 4.2.15 and 4.4.10.