There’s an issue with the popular open-source CAPTCHA software developed by MyBB. The platform is warning its users that the latest version of its software includes a CAPTCHA-breaking bug that could affect forum functionality.
MyBB CAPTCHA Bug Explained
MyBB is “the free and open source forum software powering thousands of engaging, vibrant, and unique communities across the internet.” In other words, it supports thousands of forums online, and the programming bug that appeared in version 1.8.27 could impact numerous CAPTCHA verification systems.
According to a maintenance release, “version 1.8.27 has introduced a bug affecting two of MyBB’s supported CAPTCHA mechanisms: reCAPTCHA v3 and hCaptcha invisible. For those, the CAPTCHA may appear broken, and the verification can reject or accept attempts incorrectly.”
Forums that rely on these systems should try the following steps:
temporarily switch to another mechanism using the CAPTCHA Images for Registration & Posting setting (ACP: Configuration → Settings → General Configuration), or
applying the upcoming changes to source code files manually.
Furthermore, due to a parser validation issue, forum owners should “verify that their error logging is configured properly, and monitor the log for errors that may indicate necessary changes to their customizations like custom MyCodes, theme templates, username styles, and plugins. These errors can be triggered when forum content that uses MyCode is viewed,” MyBB said.
Related: Reverse Captcha Virus