The ShopLentor WordPress plugin is vulnerable to unauthenticated email relay abuse, allowing attackers to leverage the site for spam or phishing campaigns.

This vulnerability is a CRLF injection flaw (CWE-93) located in the woolentor_suggest_price_action AJAX endpoint. Unauthenticated attackers can exploit the lack of input validation on the send_to, product_title, wlmessage, and wlemail parameters to send arbitrary emails with controlled content and headers.

The ability for an unauthenticated user to use a legitimate business domain as an email relay poses a significant risk to brand reputation and email deliverability. Attackers can leverage this flaw to send large volumes of spam or sophisticated phishing emails, potentially leading to domain blacklisting and loss of customer trust. With a CVSS score of 8.6, this is a high-severity issue that requires immediate attention to prevent unauthorized use of organizational infrastructure.

Immediate Action: Update the ShopLentor plugin to version 3.3.3 or the latest available release, which contains the necessary input validation fixes.

Proactive Monitoring: Monitor outgoing mail logs for spikes in traffic or unrecognized email content originating from the WordPress server.

Compensating Controls: Implement a Web Application Firewall (WAF) rule to block or sanitize requests to the woolentor_suggest_price_action AJAX endpoint if patching cannot be performed immediately.

Public Exploit Available: No

Given the ease with which this vulnerability can be exploited by unauthenticated actors, organizations running the ShopLentor plugin should prioritize applying the vendor-provided update. Failure to remediate this issue leaves the host system susceptible to abuse for malicious email campaigns, which can result in long-term damage to the organization's digital reputation.