Medium

Blue Captcha <= 2.0.1 - Cross-Site Request Forgery via 'blcap_action' Parameter

  • Disclosed: 23.06.2026
  • Updated: 11.10.2026 10:22

The Blue Captcha plugin for WordPress is vulnerable to Cross-Site Request Forgery in versions up to and including 2.0.1. This is due to missing or incorrect nonce validation on the main admin panel (blcap_main_page) and on the Hall of Shame and Log subpages, which accept a 'blcap_action' / 'action' parameter from $_REQUEST and perform destructive operations (plugin uninstall via blcap_uninstall(), log deletion via blcap_delete_logs(), Hall of Shame deletion via blcap_delete_ip_db(), and adding IPs to the banned list via update_option('blcap_settings')) with no wp_verify_nonce(), check_admin_referer(), or check_ajax_referer() calls anywhere in the codebase. This makes it possible for unauthenticated attackers to uninstall the plugin, delete audit logs, remove Hall of Shame entries, and add arbitrary IP addresses to the block list via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.

Affected software

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PlatformPackageVulnerable versionsFixed in
WordPress plugin Blue Captcha <= 2.0.1 2.1.0

References

CVSS score 4.3/10
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
Weakness (CWE)
CWE-352
Platform
WordPress
Package
Blue Captcha
Disclosed
23.06.2026
Updated
11.10.2026 10:22

Sources and licenses

Wordfence Intelligence - 793072e9-250b-4a2c-819f-aa7e1dc7d4d6 - Wordfence Intelligence

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Copyright 2012-2026 Defiant Inc.

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Copyright 2012-2026 Defiant Inc.

Defiant hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute this software vulnerability information. Any copy of the software vulnerability information you make for such purposes is authorized provided that you include a hyperlink to this vulnerability record and reproduce Defiant's copyright designation and this license in any such copy.

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Wordfence Intelligence
Wordfence Intelligence - Defiant, Inc.
Copyright Defiant, Inc. All rights reserved except as granted below.
License grant, section 3.1 of the Wordfence Intelligence Terms and Conditions (January 26, 2026):

Subject to this Agreement, Company hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute the Service. Any copy you make for such purposes is authorized provided that you reproduce Company’s copyright designation, this license, and the license of any disclosed Company licensor in any such copy.

Full applicable Agreement: https://www.wordfence.com/wordfence-intelligence-terms-and-conditions/

Vulnerability history: Blue Captcha

All published vulnerabilities of this package (WordPress plugin), newest first. Shows whether this is a one-off slip or a package that needs watching.

Total entries
2
First → latest
03.2025 06.2026
Without a fix
0
Exploited in attacks
0

Severity breakdown

  • Medium 2

Disclosures per year

  1. 2025: 1
  2. 2026: 1
  1. Blue Captcha <= 2.0.1 - Cross-Site Request Forgery via 'blcap_action' Parameter this entry
    Medium · 4.3 CVE-2026-10552 <= 2.0.1 2.1.0
  2. Medium · 6.1 CVE-2025-28880 <= 1.7.4 2.0.0

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