CVE-2026-4329
Blackhole for Bad Bots <= 3.8 - Unauthenticated Stored Cross-Site Scripting via User-Agent HTTP Header
Description
The Blackhole for Bad Bots plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the User-Agent HTTP header in all versions up to and including 3.8. This is due to insufficient input sanitization and output escaping. The plugin uses sanitize_text_field() when capturing bot data (which strips HTML tags but does not escape HTML entities like double quotes), then stores the data via update_option(). When an administrator views the Bad Bots log page, the stored data is output directly into HTML input value attributes (lines 75-83) without esc_attr() and into HTML span content without esc_html(). This makes it possible for unauthenticated attackers to inject arbitrary web scripts that execute when an administrator views the Blackhole Bad Bots admin page.
INFO
Published Date :
March 26, 2026, 5:16 a.m.
Last Modified :
March 26, 2026, 5:16 a.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-4329
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
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | [email protected] |
Solution
- Update the Blackhole for Bad Bots plugin.
- Remove or disable the plugin if not needed.
- Sanitize and escape all user input.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-4329.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-4329 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-2026-4329
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-2026-4329 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-4329 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.
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New CVE Received by [email protected]
Mar. 26, 2026
Action Type Old Value New Value Added Description The Blackhole for Bad Bots plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the User-Agent HTTP header in all versions up to and including 3.8. This is due to insufficient input sanitization and output escaping. The plugin uses sanitize_text_field() when capturing bot data (which strips HTML tags but does not escape HTML entities like double quotes), then stores the data via update_option(). When an administrator views the Bad Bots log page, the stored data is output directly into HTML input value attributes (lines 75-83) without esc_attr() and into HTML span content without esc_html(). This makes it possible for unauthenticated attackers to inject arbitrary web scripts that execute when an administrator views the Blackhole Bad Bots admin page. 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/blackhole-bad-bots/tags/3.8/inc/badbots-register.php#L75 Added Reference https://plugins.trac.wordpress.org/browser/blackhole-bad-bots/tags/3.8/inc/badbots-register.php#L79 Added Reference https://plugins.trac.wordpress.org/browser/blackhole-bad-bots/tags/3.8/inc/badbots-register.php#L85 Added Reference https://plugins.trac.wordpress.org/browser/blackhole-bad-bots/tags/3.8/inc/blackhole-core.php#L180 Added Reference https://plugins.trac.wordpress.org/browser/blackhole-bad-bots/tags/3.8/inc/blackhole-helpers.php#L22 Added Reference https://plugins.trac.wordpress.org/browser/blackhole-bad-bots/trunk/inc/badbots-register.php#L75 Added Reference https://plugins.trac.wordpress.org/browser/blackhole-bad-bots/trunk/inc/badbots-register.php#L79 Added Reference https://plugins.trac.wordpress.org/browser/blackhole-bad-bots/trunk/inc/badbots-register.php#L85 Added Reference https://plugins.trac.wordpress.org/browser/blackhole-bad-bots/trunk/inc/blackhole-core.php#L180 Added Reference https://plugins.trac.wordpress.org/browser/blackhole-bad-bots/trunk/inc/blackhole-helpers.php#L22 Added Reference https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&old=3487350%40blackhole-bad-bots&new=3487350%40blackhole-bad-bots&sfp_email=&sfph_mail= Added Reference https://www.wordfence.com/threat-intel/vulnerabilities/id/a71992e2-fdac-4e89-8867-4b771d9b4374?source=cve