How do I block mail that uses a bogus helo command?
The bogushelo directive determines if an e-mail should be permitted even if there is an invalid host name following the SMTP helo command. RFC 1123 section 5 2.5 says it should be. However, attackers have used bogus helo commands to perform buffer over runs to hide where the e-mail actaully came from. The default value is no.
Related Questions
- When sending mail, sometimes I am getting the following error: "Helo command rejected: need fully-qualified hostname", "Transaction Failed", or "Send Hello First" errors. How can I fix this problem?
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- How do I block mail that uses a bogus helo command?
