Nothing to see here, folks …
“Backdoor in Captcha Plugin Affects 300K WordPress Sites”
“The WordPress repository recently removed the plugin Captcha over what initially appeared to be a trademark issue with the current author using “WordPress” [Editors note: the original page has been removed, we’re now linking to a screen shot.] in their brand name.
Whenever the WordPress repository removes a plugin with a large user base, we check to see if it was possibly due to something security-related. Wordfence alerts users when any plugin they are running is removed from WordPress repo as well. At the time of its removal, Captcha had over 300,000 active installs, so its removal significantly impacts many users.”
Incredible analysis in the below link. Nicely done by WordFence.