title: DNS proxy and possible amplification attack
description: A DNS proxy and possible amplification attack vulnerability in WebClientInfo of Apache Wicket allows an attacker to trigger arbitrary DNS lookups from the server when the X-Forwarded-For header is not properly sanitized. This DNS lookup can be engineered to overload an internal DNS server or to slow down request processing of the Apache Wicket application causing a possible denial of service on either the internal infrastructure or the web application itself. This issue affects Apache Wicket Apache Wicket 9.x version 9.2.0 and prior versions; Apache Wicket 8.x version 8.11.0 and prior versions; Apache Wicket 7.x version 7.17.0 and prior versions and Apache Wicket 6.x version 6.2.0 and later versions.
problem types: DNS proxy and possible amplification attack
affected:
{
product: Apache Wicket
vendor: Apache Software Foundation
versions:
lessThanOrEqual: 9.2.0, status: affected, version: Apache Wicket 9.x, versionType: custom
lessThanOrEqual: 8.11.0, status: affected, version: Apache Wicket 8.x, versionType: custom
lessThanOrEqual: 7.17.0, status: affected, version: Apache Wicket 7.x, versionType: custom
lessThan: Apache Wicket 6.x*, status: affected, version: 6.2.0, versionType: custom
}
workarounds: Sanitize the X-Forwarded-For header by running an Apache Wicket application behind a reverse HTTP proxy. This proxy should put the client IP address in the X-Forwarded-For header and not pass through the contents of the header as received by the client.