The LiteSpeed Cache WordPress plugin before 4.4.4 does not properly verify that requests are coming from QUIC.cloud servers allowing attackers to make requests to certain endpoints by using a specific X-Forwarded-For header value. In addition one of the endpoint could be used to set CSS code if a setting is enabled which will then be output in some pages without being sanitised and escaped. Combining those two issues an unauthenticated attacker could put Cross-Site Scripting payloads in pages visited by users.