litespeedtech LiteSpeed Cache Plugin up to 7.7 on WordPress REST API Endpoint notify_ccss cross site scripting

Summaryinfo

A vulnerability marked as problematic has been reported in litespeedtech LiteSpeed Cache Plugin up to 7.7 on WordPress. This impacts an unknown function of the file /wp-json/litespeed/v1/notify_ccss of the component REST API Endpoint. The manipulation leads to cross site scripting. This vulnerability is uniquely identified as CVE-2026-3375. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability was found in litespeedtech LiteSpeed Cache Plugin up to 7.7 on WordPress. It has been rated as problematic. This issue affects an unknown code of the file /wp-json/litespeed/v1/notify_ccss of the component REST API Endpoint. The manipulation with an unknown input leads to a cross site scripting vulnerability. Using CWE to declare the problem leads to CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. Impacted is integrity. The summary by CVE is:

The LiteSpeed Cache plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the /wp-json/litespeed/v1/notify_ccss and /wp-json/litespeed/v1/notify_ucss REST API endpoints in all versions up to, and including, 7.7. These endpoints accept CSS content from QUIC.cloud callback notifications and store it to disk without sanitization. The stored content is later rendered inline frontend page loads without output escaping. The access control protecting these endpoints is IP-based validation that can potentially be bypassed when the WordPress site is deployed behind a reverse proxy, load balancer, or CDN with certain configurations. This makes it possible for unauthenticated attackers, under certain conditions, to inject arbitrary JavaScript into CCSS/UCSS content.

The weakness was disclosed by Osvaldo Noe Gonzalez Del Rio. The advisory is shared at wordfence.com. The identification of this vulnerability is CVE-2026-3375 since 02/28/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1059.007 for this issue.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

• WordPress Plugin

Vendor

• litespeedtech

Name

• LiteSpeed Cache Plugin

Version

• 7.0
• 7.1
• 7.2
• 7.3
• 7.4
• 7.5
• 7.6
• 7.7

CPE 2.3info

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CPE 2.2info

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