CVE-2026-4329 json
Blackhole for Bad Bots <= 3.8 - Unauthenticated Stored Cross-Site Scripting via User-Agent HTTP Header
published 2026-03-26 7 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-16102
- cvss
- 7.2
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 25%
- public exploits
- 0
- none known
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 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.
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 7 mo ago
Exploit prediction
0.32% chance of exploitation in the next 30 days, higher than 25% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.2 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N |
Affected products
- specialk Blackhole for Bad Bots
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
- Technology feeds
References
- wordfence.com /threat-intel/vulnerabilities/id/a71992e2-fdac-4e89-8867-4b771d9b4374?source=cve
- plugins.trac.wordpress.org /browser/blackhole-bad-bots/trunk/inc/badbots-register.php#L75
- plugins.trac.wordpress.org /browser/blackhole-bad-bots/trunk/inc/badbots-register.php#L85
- plugins.trac.wordpress.org /browser/blackhole-bad-bots/trunk/inc/badbots-register.php#L79
- plugins.trac.wordpress.org /browser/blackhole-bad-bots/tags/3.8/inc/badbots-register.php#L79
- plugins.trac.wordpress.org /browser/blackhole-bad-bots/tags/3.8/inc/badbots-register.php#L85
- plugins.trac.wordpress.org /browser/blackhole-bad-bots/tags/3.8/inc/badbots-register.php#L75
- plugins.trac.wordpress.org /browser/blackhole-bad-bots/trunk/inc/blackhole-helpers.php#L22
- plugins.trac.wordpress.org /browser/blackhole-bad-bots/tags/3.8/inc/blackhole-helpers.php#L22
- plugins.trac.wordpress.org /browser/blackhole-bad-bots/trunk/inc/blackhole-core.php#L180
- plugins.trac.wordpress.org /browser/blackhole-bad-bots/tags/3.8/inc/blackhole-core.php#L180
- plugins.trac.wordpress.org /changeset?sfp_email=&sfph_mail=&reponame=&old=3487350%40blackhole-bad-bots&new=3487350%40blackhole-bad-bots&s
Sources
- CVE List CVE-2026-4329
- NVD CVE-2026-4329
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.