CVE-2023-4372
The LiteSpeed Cache plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'esi' shortcode in versions up to, and including, 5.6 due to insufficient input sanitization and output escaping on user supplied attributes.
Does this matter?
EPSS puts the probability of exploitation in the next 30 days at 19.5%, higher than 97% of all known CVEs. Patch or mitigate before the next change window.
Description
The LiteSpeed Cache plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'esi' shortcode in versions up to, and including, 5.6 due to insufficient input sanitization and output escaping on user supplied attributes. This makes it possible for authenticated attackers with contributor-level and above permissions to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.
- CVSS 3.1
- 5.4 MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
- EPSS
- 19.50% probability · 97th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-79
- Affected
- litespeedtech/litespeed cache
- Source
- security@wordfence.com
EPSS moved from 19.3% on 24 October 2026 to 19.5% on 3 November 2026. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”.
References
- https://github.com/litespeedtech/lscache_wp/commit/95a407d9f192b37ac6cf96d2aa50f240e3e6b2d7#diff-7b2c514b58d1b8a71655607bdfab87cedb013bc1b8927ce0b49a89ddf4a7e01cR495Patch
- https://plugins.trac.wordpress.org/browser/litespeed-cache/tags/5.5.1/src/esi.cls.php#L480Issue Tracking
- https://plugins.trac.wordpress.org/changeset/2977143/litespeed-cache#file348Patch
- https://www.wordfence.com/threat-intel/vulnerabilities/id/27026f0f-c85e-4409-9973-4b9cb8a90da5?source=cveThird Party Advisory
- https://github.com/litespeedtech/lscache_wp/commit/95a407d9f192b37ac6cf96d2aa50f240e3e6b2d7#diff-7b2c514b58d1b8a71655607bdfab87cedb013bc1b8927ce0b49a89ddf4a7e01cR495Patch
- https://plugins.trac.wordpress.org/browser/litespeed-cache/tags/5.5.1/src/esi.cls.php#L480Issue Tracking
- https://plugins.trac.wordpress.org/changeset/2977143/litespeed-cache#file348Patch
- https://www.wordfence.com/threat-intel/vulnerabilities/id/27026f0f-c85e-4409-9973-4b9cb8a90da5?source=cveThird Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.