Arbitrary Shortcode Execution in CleanTalk WordPress Plugin
CVE-2026-19855

6.5MEDIUM

Key Information:

Vendor

WordPress
Status
Cleantalk
Vendor
CVE Published:
9 September 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2026-19855?

The CleanTalk WordPress plugin prior to version 6.87 is susceptible to an arbitrary shortcode execution vulnerability. This flaw allows unauthenticated users to submit comment content that is processed by the WordPress shortcode engine. As a result, malicious visitors can register and execute arbitrary shortcodes on the server-side, impacting the site’s integrity and exposing subsequent visitors to potentially harmful code rendered on the affected pages.

Affected Version(s)

CleanTalk 0 < 6.87

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2026-19855 - Proof of Concept

References

https://wpscan.com/vulnerability/c27f3657-261a-46cd-860c-...
exploitvdb-entrytechnical-description

CVSS V3.1

Score:
6.5
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
Low
Availability:
Low
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

Jakub Herman
WPScan
.