WordPress · Litespeed Cache · CVE-2021-24964
**Name of the Vulnerable Software and Affected Versions**
LiteSpeed Cache WordPress plugin versions prior to 4.4.4
**Description**
The issue arises from the plugin not properly verifying requests from QUIC.cloud servers, allowing attackers to make requests to certain endpoints by using a specific `X-Forwarded-For` header value. Additionally, an endpoint can be used to set CSS code if a setting is enabled, which will then be output in some pages without being sanitized and escaped. This can be exploited by an unauthenticated attacker to put Cross-Site Scripting payloads in pages visited by users.
**Recommendations**
For versions prior to 4.4.4, update to version 4.4.4 or later to resolve the issue. As a temporary workaround, consider disabling the setting that enables CSS code injection until a patch is available. Restrict access to the vulnerable endpoints to minimize the risk of exploitation. Avoid using the `X-Forwarded-For` header value in the affected API endpoints until the issue is resolved.