XSS in Cleantalk Spam Protection, Honeypot, Anti-Spam By
CVE-2026-77830
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.
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.2 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N.
EPSS exploit prediction
EPSS: 0.005 (39.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 40th percentile — 39.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.005 · change: +0.002
Affected products
Weakness classification (CWE)
References
- plugins.trac.wordpress.org/browser/cleantalk-spam-protect/tags/6.84/cleantalk.p…
- plugins.trac.wordpress.org/browser/cleantalk-spam-protect/tags/6.84/lib/Cleanta…
- plugins.trac.wordpress.org/browser/cleantalk-spam-protect/tags/6.84/lib/Cleanta…
- plugins.trac.wordpress.org/browser/cleantalk-spam-protect/tags/6.84/lib/Cleanta…
- plugins.trac.wordpress.org/browser/cleantalk-spam-protect/tags/6.85/cleantalk.p…
- plugins.trac.wordpress.org/browser/cleantalk-spam-protect/tags/6.85/lib/Cleanta…
- plugins.trac.wordpress.org/browser/cleantalk-spam-protect/tags/6.85/lib/Cleanta…
- plugins.trac.wordpress.org/browser/cleantalk-spam-protect/tags/6.85/lib/Cleanta…
- plugins.trac.wordpress.org/changeset/3677388/cleantalk-spam-protect/trunk/lib/C…
- plugins.trac.wordpress.org/changeset
Frequently asked questions
- What is CVE-2026-77830?
- CVE-2026-77830 is a high-severity vulnerability in Cleantalk Spam Protection, Honeypot, Anti-Spam By, classified under Cross-site Scripting. CVSS score: 7.2/10. Published 2026-09-05.
- How severe is CVE-2026-77830?
- High severity. CVSS v3 base score is 7.2 out of 10.