What is CVE-2026-19855?

CVE-2026-19855 is a medium-severity vulnerability in Cleantalk, classified under CWE-74 IMPROPER NEUTRALIZATION OF SPECIAL ELEMENTS IN OUTPUT USED BY A DOWNSTREAM COMPONENT ('INJECTION'). CVSS score: 6.5/10. Published 2026-09-09.

How severe is CVE-2026-19855?

Medium severity. CVSS v3 base score is 6.5 out of 10.

Vulnerability in Cleantalk

CVE-2026-19855

The CleanTalk WordPress plugin before 6.87 does not prevent unauthenticated, user-supplied comment content from being passed to WordPress's shortcode engine, allowing any visitor to have arbitrary shortcodes registered on the site executed server-side and rendered to every subsequent visitor of the page.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N.

Affected products

Unknown Cleantalk

References

contact@wpscan.com (technical-description, exploit, vdb-entry)

Frequently asked questions

What is CVE-2026-19855?: CVE-2026-19855 is a medium-severity vulnerability in Cleantalk, classified under CWE-74 IMPROPER NEUTRALIZATION OF SPECIAL ELEMENTS IN OUTPUT USED BY A DOWNSTREAM COMPONENT ('INJECTION'). CVSS score: 6.5/10. Published 2026-09-09.
How severe is CVE-2026-19855?: Medium severity. CVSS v3 base score is 6.5 out of 10.