CVE-2026-53533 aiosmtplib: SMTP command injection via CR/LF in sender/recipient address

aiosmtplib is an asynchronous SMTP client for use with asyncio. Prior to 5.1.1, SMTP.mail, SMTP.rcpt, SMTP.vrfy, and SMTP.expn send caller-supplied addresses without rejecting embedded CR or LF bytes. Data after the line break is framed as additional standalone SMTP command lines, allowing an...