LiteSpeed comment optimization permits unauthenticated stored XSS

LiteSpeed Cache through 7.8.1 processes crafted decimal character references inside an allowed code element into a malicious data-settings attribute. On sites where previously approved commenters can post again and require_name_email is disabled, an unauthenticated commenter can store script that executes for page visitors.

CVE / CNA score 7.2 CVSS 3.1 · security@wordfence.com

NVD score Pending NVD has not published its own CVSS assessment.

Component: LiteSpeed Cache
Plugin slug: litespeed-cache
Affected: <= 7.8.1
Safe version: See mitigation notes
Published: Aug 28, 2026
Weakness: CWE-79 — Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

This CVE was published Aug 28, 2026 and is one of 23 known issues for this plugin.

What to do

Update, patch or deactivate.

No fixed release is confirmed. Update LiteSpeed Cache when a release after 7.8.1 is confirmed to fix the issue; until then, moderate comments and disable the affected comment or media processing path when warranted.

No confirmed safe version is listed. Consider a vendor-supported patch or temporarily restricting the affected functionality while you assess the risk.

Deactivate only when warranted by your risk profile, or when advised by your hosting provider in the limited circumstances where the vulnerability cannot otherwise be mitigated. If you’re unsure which action is appropriate, contact Fused or your hosting provider for guidance.

Source record

Technical description

The LiteSpeed Cache plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Comment Content in all versions up to, and including, 7.8.1 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. A comment payload crafted exclusively from decimal numeric character references (e.g. ", <, >) placed inside an allowed element such as <code> bypasses WordPress's wp_kses sanitization, as kses does not treat a data-settings="..." substring within text content as an HTML attribute, allowing the malicious payload to reach the vulnerable function. For this to be exploitable, the site must allow users with previously approved comments to write new comments, and the require_name_email setting must be disabled.

CVE / CNA vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N

References

Primary and upstream sources

Data attribution: This product uses the NVD API but is not endorsed or certified by the NVD.

Vulnerability data licensing

CVE. Copyright © 1999–2026, The MITRE Corporation. MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy.

CWE. Copyright © 2006–2026, The MITRE Corporation. CWE™ is free to use by any organization or individual for any research, development, and/or commercial purposes, per these CWE Terms of Use. Accordingly, The MITRE Corporation hereby grants you a non-exclusive, royalty-free license to use CWE for research, development, and commercial purposes. Any copy you make for such purposes is authorized on the condition that you reproduce MITRE’s copyright designation and this license in any such copy.

CVSS. CVSS is owned and managed by FIRST.Org, Inc. (FIRST) and used by permission.

Source-record text is CVE/CNA content delivered through the NVD API. Fused summaries and remediation guidance are independently authored and are not attributed to NVD.

All other copyrights and trademarks are the property of their respective owners.

Full data sources, terms, and disclaimers