CSS Parser: Improper Certificate Validation allows MITM injection of remote CSS content

Summary The CSS Parser gem does not validate HTTPS connections, allowing a Man-in-the-Middle MITM attacker to inject or modify CSS content when stylesheets are loaded via HTTPS. The connection is established with OpenSSL::SSL::VERIFYNONE, meaning any HTTPS certificate—even entirely untrusted—will...

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...