WordPress security changelog
HIGH CVE-2026-4329 Deferred

Blackhole for Bad Bots: Cross-site scripting

Blackhole for Bad Bots is affected by cross-site scripting. The vulnerable path is reachable without authentication. Injected script can execute in the affected site's origin when the vulnerable output is viewed. The published affected range is <= 3.8.

CVE / CNA score 7.2 CVSS 3.1 · security@wordfence.com
NVD score Pending NVD has not published its own CVSS assessment.
Component
Blackhole for Bad Bots
Plugin slug
blackhole-bad-bots
Affected
<= 3.8
Safe version
> 3.8
Published
Mar 26, 2026
Weakness
CWE-79 — Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

This CVE was published Mar 26, 2026 and is one of 1 known issue for this plugin.

What to do

Update, patch or deactivate.

Update Blackhole for Bad Bots to a release after 3.8, or disable and remove it until a fixed version is available.

A safe version is available, so updating to that version or later is the preferred remediation. If an immediate update is not practical, consider a targeted application patch or temporarily restricting the affected functionality.

Deactivate only when warranted by your risk profile, or when advised by your hosting provider in the limited circumstances where the vulnerability cannot otherwise be mitigated. If you’re unsure which action is appropriate, contact Fused or your hosting provider for guidance.

Source record

Technical 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.

CVE / CNA vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N

References

Primary and upstream sources