Unit 4 Assignment 1: Smtp Security Best Practices
Question 1 Answer:
1. Viruses
Viruses have been around for a long time, and can render a system useless if not dealt with. New, more destructive viruses and worms are being unleashed exponentially. Reports indicate that 50 percent more virus attacks were launched in 2003 than the prior year. The January-March 2004 Mydoom virus outbreaks were the biggest the Internet has encountered to date.
2. Spam
Spam is expected to increase to 80 to 90 percent of total email. New viruses turn desktop PCs into spam-spewing "zombies." There is also a new type of spamming technique called "phishing," used to dupe recipients into providing confidential personal identity information. You can expect the occurrence of these spam-virus hybrids to increase and develop into even more dangerous and damaging threats
3. Directory Harvest Attacks (DHAs)
Also called "dictionary attacks," this technique steals proprietary information from corporate directories. During a DHA, spammers attempt to deliver messages to multiple addresses, such as johndoe@yourcompany.com, jdoe@yourcompany.com, and john@yourcompany.com. Addresses that are not rejected by the receiving mail server are determined to be valid. These addresses are compiled and sold to other spammers worldwide; companies who have had their email addresses harvested are vulnerable to an ever-growing amount of junk mail. An estimated 30 to 40 percent of inbound SMTP connections through the corporate mail gateway can be traced to DoS and DHA attacks. These threats can overwhelm mail transfer agents (email servers) to the point of shutdown.
Question 2 Answer:
1. Disable open relaying on all SMTP virtual servers.
2. Prevent anonymous access on internal SMTP virtual servers and dedicated SMTP virtual servers for IMAP and POP clients.
3. Digitally sign and encrypt your Email.
Question 3 Answer:
You are going to allow your remote users to relay mail via your mail server across the internet, as this will encrypt the username and
1. Viruses
Viruses have been around for a long time, and can render a system useless if not dealt with. New, more destructive viruses and worms are being unleashed exponentially. Reports indicate that 50 percent more virus attacks were launched in 2003 than the prior year. The January-March 2004 Mydoom virus outbreaks were the biggest the Internet has encountered to date.
2. Spam
Spam is expected to increase to 80 to 90 percent of total email. New viruses turn desktop PCs into spam-spewing "zombies." There is also a new type of spamming technique called "phishing," used to dupe recipients into providing confidential personal identity information. You can expect the occurrence of these spam-virus hybrids to increase and develop into even more dangerous and damaging threats
3. Directory Harvest Attacks (DHAs)
Also called "dictionary attacks," this technique steals proprietary information from corporate directories. During a DHA, spammers attempt to deliver messages to multiple addresses, such as johndoe@yourcompany.com, jdoe@yourcompany.com, and john@yourcompany.com. Addresses that are not rejected by the receiving mail server are determined to be valid. These addresses are compiled and sold to other spammers worldwide; companies who have had their email addresses harvested are vulnerable to an ever-growing amount of junk mail. An estimated 30 to 40 percent of inbound SMTP connections through the corporate mail gateway can be traced to DoS and DHA attacks. These threats can overwhelm mail transfer agents (email servers) to the point of shutdown.
Question 2 Answer:
1. Disable open relaying on all SMTP virtual servers.
2. Prevent anonymous access on internal SMTP virtual servers and dedicated SMTP virtual servers for IMAP and POP clients.
3. Digitally sign and encrypt your Email.
Question 3 Answer:
You are going to allow your remote users to relay mail via your mail server across the internet, as this will encrypt the username and