Description
WordPress Plugin MailPoet Newsletters (Previous) is prone to a security bypass vulnerability. Exploiting this issue may allow attackers to perform otherwise restricted actions and subsequently subscribe arbitrary users without their specific consent. WordPress Plugin MailPoet Newsletters (Previous) version 2.8.1 is vulnerable; prior versions may also be affected.
Remediation
Update to plugin version 2.8.2 or latest
References
https://eredasecurity.wordpress.com/2018/03/17/mailpoet-spamming-vulnerability/
https://plugins.svn.wordpress.org/wysija-newsletters/trunk/readme.txt
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