The Contact Form 7 Captcha WordPress plugin before 0.0.9 does not have any CSRF check in place when saving its settings, allowing attacker to make a logged in user with the manage_options change them. Furthermore, the settings are not escaped when output in attributes, leading to a Stored Cross-Site Scripting issue.

An XSS issue was discovered in ReCaptcha Solver 5.7. A response from Anti-Captcha.com, RuCaptcha.com, 2captcha.com, DEATHbyCAPTCHA.com, ImageTyperz.com, or BestCaptchaSolver.com in setCaptchaCode() is inserted into the DOM as HTML, resulting in full control over the user's browser by these servers.

omr-admin.py in openmptcprouter-vps-admin 0.57.3 and earlier compares the user provided password with the original password in a length dependent manner, which allows remote attackers to guess the password via a timing attack.

KEPServerEX: v6.0 to v6.9, ThingWorx Kepware Server: v6.8 and v6.9, ThingWorx Industrial Connectivity: All versions, OPC-Aggregator: All versions, Rockwell Automation KEPServer Enterprise, GE Digital Industrial Gateway Server: v7.68.804 and v7.66, Software Toolbox TOP Server: All 6.x versions are vulnerable to a stack-based buffer overflow. Opening a specifically crafted OPC UA message could allow an attacker to crash the server and remotely execute code.

KEPServerEX: v6.0 to v6.9, ThingWorx Kepware Server: v6.8 and v6.9, ThingWorx Industrial Connectivity: All versions, OPC-Aggregator: All versions, Rockwell Automation KEPServer Enterprise, GE Digital Industrial Gateway Server: v7.68.804 and v7.66, Software Toolbox TOP Server: All 6.x versions, are vulnerable to a heap-based buffer overflow. Opening a specifically crafted OPC UA message could allow an attacker to crash the server and potentially leak data.

KEPServerEX v6.0 to v6.9, ThingWorx Kepware Server v6.8 and v6.9, ThingWorx Industrial Connectivity (all versions), OPC-Aggregator (all versions), Rockwell Automation KEPServer Enterprise, GE Digital Industrial Gateway Server v7.68.804 and v7.66, and Software Toolbox TOP Server all 6.x versions, are vulnerable to a heap-based buffer overflow. Opening a specifically crafted OPC UA message could allow an attacker to crash the server and potentially leak data.

The jh_captcha extension through 2.1.3, and 3.x through 3.0.2, for TYPO3 allows XSS.

The simple_captcha2 gem 0.2.3 for Ruby, as distributed on RubyGems.org, included a code-execution backdoor inserted by a third party.

The PS PHPCaptcha WP plugin before v1.2.0 for WordPress mishandles sanitization of input values.

text/impl/DefaultTextCreator.java, text/impl/ChineseTextProducer.java, and text/impl/FiveLetterFirstNameTextCreator.java in kaptcha 2.3.2 use the Random (rather than SecureRandom) function for generating CAPTCHA values, which makes it easier for remote attackers to bypass intended access restrictions via a brute-force approach.