Strip CRLF from message headers in SmtpTransport - #19512
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Strip CRLF bytes from message headers when delivering mail by SmtpTransport. This prevents header injection should userland code supply user data into messages headers. Thank you to Himanshu Anand for reporting this issue.
ADmad
approved these changes
Jun 26, 2026
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Strip CRLF bytes from message headers when delivering mail by SmtpTransport. This prevents header injection should userland code supply user data into messages headers. I've extended the test coverage for this scenario as well.
Thank you to Himanshu Anand for reporting this issue.