7.2
HIGH CVSS 3.1
CVE-2026-13042
RPB Chessboard <= 8.1.2 - Unauthenticated Stored Cross-Site Scripting via Comment Content
Description

The RPB Chessboard plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Comment Content in all versions up to, and including, 8.1.2 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. WordPress's save-time kses sanitization does not mitigate this issue because the crafted payload uses only kses-allowed tags and attributes (such as an &lt;a&gt; element with title and href), and the dangerous attribute-breaking HTML is synthesized entirely at render time by the plugin's own comment_text filter.

INFO

Published Date :

July 16, 2026, 5:16 a.m.

Last Modified :

July 16, 2026, 5:16 a.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-13042 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH [email protected]
Solution
Update the RPB Chessboard plugin to a version that addresses the Stored Cross-Site Scripting vulnerability.
  • Update the RPB Chessboard plugin to the latest version.
  • Apply security patches provided by the vendor.
  • Sanitize all user-supplied input.
  • Escape all output to prevent script execution.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-13042 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-13042 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-13042 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-13042 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Jul. 16, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'yo35', 'product': 'RPB Chessboard', 'versions': [{'status': 'affected', 'version': '0', 'versionType': 'semver', 'lessThanOrEqual': '8.1.2'}], 'defaultStatus': 'unaffected'}]
    Added Description The RPB Chessboard plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Comment Content in all versions up to, and including, 8.1.2 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. WordPress's save-time kses sanitization does not mitigate this issue because the crafted payload uses only kses-allowed tags and attributes (such as an &lt;a&gt; element with title and href), and the dangerous attribute-breaking HTML is synthesized entirely at render time by the plugin's own comment_text filter.
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
    Added CWE CWE-79
    Added Reference https://plugins.trac.wordpress.org/browser/rpb-chessboard/tags/8.1.0/php/abstractcontroller.php#L171
    Added Reference https://plugins.trac.wordpress.org/browser/rpb-chessboard/tags/8.1.0/php/abstractcontroller.php#L190
    Added Reference https://plugins.trac.wordpress.org/browser/rpb-chessboard/tags/8.1.0/php/abstractcontroller.php#L220
    Added Reference https://plugins.trac.wordpress.org/browser/rpb-chessboard/tags/8.1.2/php/abstractcontroller.php#L171
    Added Reference https://plugins.trac.wordpress.org/browser/rpb-chessboard/tags/8.1.2/php/abstractcontroller.php#L190
    Added Reference https://plugins.trac.wordpress.org/browser/rpb-chessboard/tags/8.1.2/php/abstractcontroller.php#L220
    Added Reference https://plugins.trac.wordpress.org/changeset?reponame=&old=3604068%40rpb-chessboard&new=3604068%40rpb-chessboard
    Added Reference https://www.wordfence.com/threat-intel/vulnerabilities/id/848b9c6d-e0db-43ad-ac6d-3674435339dd?source=cve
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.