CVE-2026-66599: CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in Liquid Web / StellarWP WPComplete
Unauthenticated Cross Site Scripting (XSS) in WPComplete <= 2.9.5.6 versions.
AI Analysis
Technical Summary
This vulnerability, identified as CWE-79, affects WPComplete plugin for WordPress developed by Liquid Web / StellarWP. It allows unauthenticated attackers to perform cross-site scripting attacks by exploiting improper neutralization of input during web page generation. The vulnerability impacts WPComplete versions up to 2.9.5.6. No official patch or remediation guidance is currently provided in the available data.
Potential Impact
Successful exploitation could lead to partial confidentiality, integrity, and availability impacts as indicated by the CVSS vector (C:L/I:L/A:L). Specifically, attackers may execute arbitrary scripts in the context of the affected site, potentially leading to session hijacking, defacement, or other malicious actions affecting users and site integrity.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, consider applying web application firewall (WAF) rules to detect and block XSS payloads targeting WPComplete or disabling the plugin if feasible.
CVE-2026-66599: CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in Liquid Web / StellarWP WPComplete
Description
Unauthenticated Cross Site Scripting (XSS) in WPComplete <= 2.9.5.6 versions.
CVSS v3.1
Score 7.1high
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability, identified as CWE-79, affects WPComplete plugin for WordPress developed by Liquid Web / StellarWP. It allows unauthenticated attackers to perform cross-site scripting attacks by exploiting improper neutralization of input during web page generation. The vulnerability impacts WPComplete versions up to 2.9.5.6. No official patch or remediation guidance is currently provided in the available data.
Potential Impact
Successful exploitation could lead to partial confidentiality, integrity, and availability impacts as indicated by the CVSS vector (C:L/I:L/A:L). Specifically, attackers may execute arbitrary scripts in the context of the affected site, potentially leading to session hijacking, defacement, or other malicious actions affecting users and site integrity.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, consider applying web application firewall (WAF) rules to detect and block XSS payloads targeting WPComplete or disabling the plugin if feasible.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Patchstack
- Date Reserved
- 2026-07-27T14:00:08.990Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a8c3087acd9273b497933f7
Added to database: 08/24/2026, 11:52:39 UTC
Last enriched: 08/24/2026, 12:07:26 UTC
Last updated: 08/25/2026, 02:51:59 UTC
Views: 6
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