One of the changelog entries for the latest version of Login No Captcha reCAPTCHA is “Resolve issue introduced in 1.4x whereby captcha was being be bypassed”. Looking at the changes made in that version we were not sure which of those might be related to that. In testing things out we found that changing this line from:

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This post provides insights on a vulnerability in the WordPress plugin CAPTCHA Bypass not discovered by us, where the discoverer hadn't provided the details needed for us to confirm the vulnerability while we were adding it to the data set for our service, so the rest of its contents are limited to subscribers of our service.

If you were using our service, you would have already been warned about this vulnerability if your website is vulnerable due to it. You can try out our service for free and then see the rest of the details of the vulnerability.

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