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CVE-2026-4329 - Blackhole Bad Bots Plugin

CVE-2026-4329

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-2026-4329

HIGH CVSS 7.2 Published 2026-03-26 Updated 2026-03-30
AI Risk Elevated (72/100) Active Exploit: No strong signal Published Exploit: No public exploit references Priority: P3 Priority
Severity Band HIGH
CVSS Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
Affected Components 2
Reference Links 10
AI Risk Engine Elevated (72/100)
Exploitability Medium
Active Exploitation No strong signal
Published Exploit Status No public exploit references

Threat Timeline

  1. 2026-03-26 CVE published and first recorded in the threat feed.
  2. 2026-03-30 Record updated with latest vulnerability metadata.
  3. 2026-04-09 AI technical context refreshed for mitigation and impact guidance.
  4. Now Monitoring for follow-up changes, linked references, and new related CVEs.

AI Context

Machine-generated threat intelligence

AI Updated 6 days ago

AI enriched 6 days ago (2026-04-09 06:08 UTC)

Technical Summary

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…

Potential Impact

Severity is HIGH (CVSS 7.2). Depending on deployment context, affected components may be exposed to unauthorized actions or data integrity risk.

Exploitability Assessment

Exploitability is assessed as Medium based on low-bar exploit prerequisites.

Primary risk drivers: low-bar exploit prerequisites

Mitigation Recommendations

Validate affected product versions, prioritize patching, and monitor references for vendor remediation guidance. If immediate patching is not possible, apply compensating controls and limit exposure of vulnerable surfaces.

Detection & Monitoring

Track authentication anomalies, unexpected file writes, and suspicious plugin API activity around affected components.

Business Impact Lens

Prioritize remediation where affected components process customer data, admin sessions, or Internet-exposed workflows.

Affected Products

Blackhole Bad Bots PLUGIN · blackhole-bad-bots Affected: <= 3.8 Fixed version not specified
Blackhole For Bad Bots PLUGIN · blackhole-for-bad-bots Affected: <= 3.8 Fixed version not specified

References

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