aiosmtpd STARTTLS unencrypted commands injection
Servers based on aiosmtpd accept extra unencrypted commands after STARTTLS, treating them as if they came from inside the encrypted connection. This could be exploited by a MitM attack.
Servers based on aiosmtpd accept extra unencrypted commands after STARTTLS, treating them as if they came from inside the encrypted connection. This could be exploited by a MitM attack.
Summary aiosmtpd is vulnerable to inbound SMTP smuggling. SMTP smuggling is a novel vulnerability based on not so novel interpretation differences of the SMTP protocol. By exploiting SMTP smuggling, an attacker may send smuggle/spoof e-mails with fake sender addresses, allowing advanced phishing attacks. This issue also existed in other SMTP software like Postfix (https://www.postfix.org/smtp-smuggling.html). Details Detailed information on SMTP smuggling can be found in the full blog post (https://sec-consult.com/blog/detail/smtp-smuggling-spoofing-e-mails-worldwide/) or …