{"api_version":"1","generated_at":"2026-08-22T04:27:13+00:00","cve":"CVE-2026-53533","urls":{"html":"https://cve.report/CVE-2026-53533","api":"https://cve.report/api/cve/CVE-2026-53533.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-53533","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-53533"},"summary":{"title":"aiosmtplib: SMTP command injection via CR/LF in sender/recipient address","description":"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 attacker who influences an envelope sender or recipient to inject commands such as MAIL FROM, RCPT TO, RSET, DATA, or AUTH. 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