Monthly
CAPTCHA challenge controls in Discuz! X5.0 (releases 20260320-20260501) can be reliably defeated by unauthenticated remote attackers who harvest samples from exposed forum endpoints and train a custom optical character recognition model to predict challenge text. The underlying weakness - CWE-804 - stems from a limited, predictable character set and insufficient visual distortion in generated images, enabling automation of login, registration, and other abuse-protected flows. Critically, a publicly available exploit exists and KarmaInsecurity has documented chaining this bypass with a race condition to achieve full remote code execution, substantially elevating practical risk beyond the standalone CVSS 4.0 score of 6.9.
WWBN AVideo is an open source video platform. In versions 29.0 and prior, `objects/getCaptcha.php` accepts the CAPTCHA length (`ql`) directly from the query string with no clamping or sanitization, letting any unauthenticated client force the server to generate a 1-character CAPTCHA word. Combined with a case-insensitive `strcasecmp` comparison over a ~33-character alphabet and the fact that failed validations do NOT consume the stored session token, an attacker can trivially brute-force the CAPTCHA on any endpoint that relies on `Captcha::validation()` (user registration, password recovery, contact form, etc.) in at most ~33 requests per session. Commit bf1c76989e6a9054be4f0eb009d68f0f2464b453 contains a fix.
If the anti spam-captcha functionality in PluXml versions 5.8.22 and earlier is enabled, a captcha challenge is generated with a format that can be automatically recognized for articles, such that an automated script is able to solve this anti-spam mechanism trivially and publish spam comments. [CVSS 5.3 MEDIUM]
The SiteGuard WP Plugin for WordPress through version 1.7.9 contains a guessable CAPTCHA implementation that allows attackers to bypass security protections without authentication. This vulnerability enables attackers to circumvent the plugin's functionality controls and potentially gain unauthorized access to protected resources or perform actions that should be restricted.
DNN (formerly DotNetNuke) is an open-source web content management platform (CMS) in the Microsoft ecosystem. Rated medium severity (CVSS 4.2), this vulnerability is remotely exploitable, no authentication required.
The Advanced Google reCaptcha plugin for WordPress is vulnerable to CAPTCHA Bypass in versions up to, and including, 1.27 . Rated medium severity (CVSS 5.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Guessable CAPTCHA vulnerability in BestWebSoft Captcha by BestWebSoft allows Functionality Bypass.2.0. Rated medium severity (CVSS 5.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Guessable CAPTCHA vulnerability in Guido VS Contact Form allows Functionality Bypass.7. Rated medium severity (CVSS 5.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
The Getwid - Gutenberg Blocks plugin for WordPress is vulnerable to CAPTCHA Bypass in versions up to, and including, 2.0.4. Rated medium severity (CVSS 5.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
The Appointment Hour Booking plugin for WordPress is vulnerable to CAPTCHA bypass in versions up to, and including, 1.3.72. Rated medium severity (CVSS 5.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
CAPTCHA challenge controls in Discuz! X5.0 (releases 20260320-20260501) can be reliably defeated by unauthenticated remote attackers who harvest samples from exposed forum endpoints and train a custom optical character recognition model to predict challenge text. The underlying weakness - CWE-804 - stems from a limited, predictable character set and insufficient visual distortion in generated images, enabling automation of login, registration, and other abuse-protected flows. Critically, a publicly available exploit exists and KarmaInsecurity has documented chaining this bypass with a race condition to achieve full remote code execution, substantially elevating practical risk beyond the standalone CVSS 4.0 score of 6.9.
WWBN AVideo is an open source video platform. In versions 29.0 and prior, `objects/getCaptcha.php` accepts the CAPTCHA length (`ql`) directly from the query string with no clamping or sanitization, letting any unauthenticated client force the server to generate a 1-character CAPTCHA word. Combined with a case-insensitive `strcasecmp` comparison over a ~33-character alphabet and the fact that failed validations do NOT consume the stored session token, an attacker can trivially brute-force the CAPTCHA on any endpoint that relies on `Captcha::validation()` (user registration, password recovery, contact form, etc.) in at most ~33 requests per session. Commit bf1c76989e6a9054be4f0eb009d68f0f2464b453 contains a fix.
If the anti spam-captcha functionality in PluXml versions 5.8.22 and earlier is enabled, a captcha challenge is generated with a format that can be automatically recognized for articles, such that an automated script is able to solve this anti-spam mechanism trivially and publish spam comments. [CVSS 5.3 MEDIUM]
The SiteGuard WP Plugin for WordPress through version 1.7.9 contains a guessable CAPTCHA implementation that allows attackers to bypass security protections without authentication. This vulnerability enables attackers to circumvent the plugin's functionality controls and potentially gain unauthorized access to protected resources or perform actions that should be restricted.
DNN (formerly DotNetNuke) is an open-source web content management platform (CMS) in the Microsoft ecosystem. Rated medium severity (CVSS 4.2), this vulnerability is remotely exploitable, no authentication required.
The Advanced Google reCaptcha plugin for WordPress is vulnerable to CAPTCHA Bypass in versions up to, and including, 1.27 . Rated medium severity (CVSS 5.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Guessable CAPTCHA vulnerability in BestWebSoft Captcha by BestWebSoft allows Functionality Bypass.2.0. Rated medium severity (CVSS 5.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Guessable CAPTCHA vulnerability in Guido VS Contact Form allows Functionality Bypass.7. Rated medium severity (CVSS 5.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
The Getwid - Gutenberg Blocks plugin for WordPress is vulnerable to CAPTCHA Bypass in versions up to, and including, 2.0.4. Rated medium severity (CVSS 5.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
The Appointment Hour Booking plugin for WordPress is vulnerable to CAPTCHA bypass in versions up to, and including, 1.3.72. Rated medium severity (CVSS 5.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity.