The MemberHero WordPress plugin through 6.9 does not perform any capability or nonce check on one of its AJAX actions, allowing any authenticated user, such as a subscriber, to make the site send arbitrary HTML emails to arbitrary recipients from its own mail system, which can be abused to relay phishing carrying the site's identity and domain reputation.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
Low
Basic privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
None
No data leak
Integrity
Low
Partial data modification
Availability
None
No disruption
CVSS Vector v3.1
Weakness Type (CWE)
Vulnerable Products
unknown:memberhero