CVE-2026-45709 Mailpit has an incomplete fix for GHSA-6jxm: HTML check still permits SSRF to private/loopback/IMDS via missing IP-filter dialer

Mailpit is an email testing tool and API for developers. The fix for GHSA-6jxm-fv7w-rw5j CVE-2026-23845, "Server-Side Request Forgery SSRF via HTML Check API", shipped in mailpit v1.28.3, hardened internal/htmlcheck/css.go::downloadCSSToBytes with a 5MB size cap, a text/css content-type check,...

Server-Side Request Forgery (SSRF)

github.com/axllent/mailpit is vulnerable to Server-Side Request Forgery SSRF. The vulnerability is due to the HTML Check feature automatically downloading remote CSS resources without proper validation, which allows an attacker to embed malicious stylesheet links in emails and trigger unauthorize...

GHSA-6JXM-FV7W-RW5J Mailpit has a Server-Side Request Forgery (SSRF) via HTML Check API

Server-Side Request Forgery SSRF via HTML Check CSS Download The HTML Check feature /api/v1/message/ID/html-check is designed to analyze HTML emails for compatibility. During this process, the inlineRemoteCSS function automatically downloads CSS files from external tags to inline them for testing...

EUVD-2026-3296

Mailpit has a Server-Side Request Forgery SSRF via HTML Check API...

CVE-2026-23845

Mailpit is an email testing tool and API for developers. Versions prior to 1.28.3 are vulnerable to Server-Side Request Forgery SSRF via HTML Check CSS Download. The HTML Check feature /api/v1/message/ID/html-check is designed to analyze HTML emails for compatibility. During this process, the...

CVE-2026-23845 Mailpit Vulnerable to Server-Side Request Forgery (SSRF) via HTML Check API

Mailpit is an email testing tool and API for developers. Versions prior to 1.28.3 are vulnerable to Server-Side Request Forgery SSRF via HTML Check CSS Download. The HTML Check feature /api/v1/message/ID/html-check is designed to analyze HTML emails for compatibility. During this process, the...

CVE-2026-23845 Mailpit Vulnerable to Server-Side Request Forgery (SSRF) via HTML Check API

Mailpit is an email testing tool and API for developers. Versions prior to 1.28.3 are vulnerable to Server-Side Request Forgery SSRF via HTML Check CSS Download. The HTML Check feature /api/v1/message/ID/html-check is designed to analyze HTML emails for compatibility. During this process, the...