CVE-2026-3375 json
LiteSpeed Cache <= 7.7 - Unauthenticated Stored Cross-Site Scripting via QUIC.cloud CCSS/UCSS REST API Endpoints
published 2026-05-27 5 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-32115
- cvss
- 7.2
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 29%
- public exploits
- 0
- none known
Summary
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.
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 5 mo ago
Exploit prediction
0.36% chance of exploitation in the next 30 days, higher than 29% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.2 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N |
Affected products
- litespeedtech LiteSpeed Cache
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
- Technology feeds
References
- wordfence.com /threat-intel/vulnerabilities/id/40fa29f5-525a-4986-91f9-0210a7594e46?source=cve
- plugins.trac.wordpress.org /browser/litespeed-cache/trunk/src/rest.cls.php#L108
- plugins.trac.wordpress.org /browser/litespeed-cache/trunk/src/cloud.cls.php#L2085
- plugins.trac.wordpress.org /browser/litespeed-cache/trunk/src/css.cls.php#L401
- plugins.trac.wordpress.org /browser/litespeed-cache/trunk/src/css.cls.php#L595
- plugins.trac.wordpress.org /browser/litespeed-cache/trunk/src/optimize.cls.php#L477
- plugins.trac.wordpress.org /browser/litespeed-cache/trunk/src/router.cls.php#L732
- plugins.trac.wordpress.org /changeset/3473912/
Sources
- CVE List CVE-2026-3375
- NVD CVE-2026-3375
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.