in src/main/java/org/apache/sling/security/impl/ReferrerFilter.java [468:476]
private boolean isValidRegexReferrer(HostInfo hostInfo) {
for (final Pattern ref : this.allowedRegexReferrers) {
String url = hostInfo.toURI();
if (ref.matcher(url).matches()) {
return true;
}
}
return false;
}