Vulnerability in LiteSpeed Cache — CVE-2026-3129
MediumSeverity
0.2%Estimated exploit probability
7,000,000+ sitesInstalls
7.8Fixed in
What to do now
Update LiteSpeed Cache to 7.8 or later.
Affected versions
- Everything up to and including 7.7
Affected: LiteSpeed Cache (plugin, litespeed-cache)
What the vulnerability is
The LiteSpeed Cache plugin for WordPress is vulnerable to Stored Cross-Site Scripting via crafted `<img>` tag attributes in all versions up to, and including, 7.7. This is due to a flawed regular expression that is used to strip `width` and `height` attributes from images when the "Lazy Load Images" and "Add Missing Sizes" features are enabled. This makes it possible for authenticated attackers, with Author-level access and above, to inject arbitrary web scripts in pages that execute whenever a user accesses an injected page.
Sources
- https://blog.litespeedtech.com/2026/08/27/security-update-for-lscwp-cve-2026-3129/
- https://plugins.trac.wordpress.org/browser/litespeed-cache/trunk/src/media.cls.php#L761
- https://plugins.trac.wordpress.org/changeset/3473912/
- https://www.wordfence.com/threat-intel/vulnerabilities/id/c107674d-173f-49cf-b329-e7bffaee841d?source=cve