CVE-2026-77830: cleantalk spam protection, honeypot, anti-spam by cleantalk Cross-site Scripting

Vulnerability summary

CVE-2026-77830 is a high (CVSS 7.2) Cross-site Scripting vulnerability in cleantalk spam protection, honeypot, anti-spam by cleantalk. EPSS estimates a 0.47% chance of exploitation in the next 30 days, higher than 39.9% of scored vulnerabilities. Fixed in 6.87.

Timeline

1. 05-09-2026
   PublishedVulnerability first disclosed.
2. 08-09-2026
   Last modifiedVulnerability information updated.

Description

The Spam protection, Honeypot, Anti-Spam by CleanTalk plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Comment Content aria-label Placeholder in all versions up to, and including, 6.86 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with custom-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The payload is deliverable via unauthenticated comment submission and executes exclusively for non-logged-in visitors; if comment moderation is enabled, an approving moderator must first publish the comment before the script reaches other users.

• CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.