MailerSend – Official SMTP Integration
MailerSend – Official SMTP Integration has one disclosed vulnerability in the WordSec catalog, all reported in 2026; it is fixed as of September 2026. Their average CVSS score is 4.3, and the most serious one scores 4.3 out of 10.
The most common weakness is Cross-Site Request Forgery (CSRF), behind 1 of the records (100%).
The one issue recorded for MailerSend – Official SMTP Integration has a vendor fix available, so running the current release closes it.
All of these findings were reported by Huynh Kien Minh. MailerSend – Official SMTP Integration is installed on roughly 2,000 WordPress sites, so each unpatched flaw has a wide blast radius. The current release is tested up to WordPress 6.9.7.
CVE-2026-13156MailerSend - Official SMTP Integration <= 1.0.7 - Cross-Site Request Forgery
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MailerSend – Official SMTP Integration
Author
MailerSend
WordPress hosting companies are not optimized for high-volume email sending, which may result in some of your emails not getting delivered. MailerSend’s dedicated SMTP server will ensure that your forms, account notifications, e-commerce orders, and other transactional emails get delivered. By using this official SMTP plugin, you will: * Improve your email deliverability * Protect your domain reputation * Learn more about your recipients Deliverability Improve inbox performance and ensure a smooth customer experience by letting MailerSend take care of email sending. After a decade of email delivery experience, MailerSend’s deliverability experts understand what it takes to avoid spam filters, stay off blocklists and lower bounce rates. Domain reputation Keep your domain reputation safe with MailerSend’s email authentication practices. Give your customers the confidence that they’re interacting with an established brand, and let MailerSend manage the emails that could potentially damage your reputation. Analytics Understand what happens after an email gets sent. Access a wide range of key metrics—like open rates, bounce rates and click-through rates—to learn what works and what needs optimization so you can keep improving your email performance. Features Avoid spam filters, prevent blocklisting, and lower hard bounce rates with powerful sending infrastructure Automate the customer experience by connecting to thousands of other apps with Zapier Get instant push updates with webhooks Receive customer replies sent to your domain with an inbound route feature Monitor all email interactions such as opens, clicks, open locations and devices. Plus, use your own subdomain and get a custom tracking link! How it works Install and activate the MailerSend plugin. Add your SMTP credentials from MailerSend to establish the connection. Test your connection to make sure it’s working. And get sending! Support Get help whenever you need it. Contact us or drop a message via live chat in the app. MailerSend’s dedicated support team works 24/7 because transactional emails never stop.
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