Email Security
1. Understanding Email
Electronic mail or email is a means of sending a letter sent through a computer network (eg Internet). By regular mail, the sender generally need to pay per delivery (by buying stamps), but electronic mail is generally the cost is the cost to pay for an Internet connection.
Electronic mail or email is a means of sending a letter sent through a computer network (eg Internet). By regular mail, the sender generally need to pay per delivery (by buying stamps), but electronic mail is generally the cost is the cost to pay for an Internet connection.
2. Email Format
Is defined by RFC 822• headerSuch as envelopes, containing information about the sender and the destination address.• BodyThe contents of the letter. Separated from the header by an empty line.
3. Email System
In the process of sending messages from the sender to the receiver, there is the system used. There are two components contained in the email system are:
1. Mail User Agent (MUA)
Associated with the user. Example: mutt, pine, Pegasus, Eudora, Netscape, outlook, thunderbird.
2. Mail Transfer Agent (MTA)
What do the mail delivery. Example: sendmail, qmail, postfix, exchange.
4. Email Protocol (brief review)
Some of the protocols involved in sending mail: SMTP and POP or IMAP
• SMTP- Simple Mail Transfer Protocol.- Used for mail delivery between servers. Email clients retrieve mail from the server using the POP protocol IMAP
• POP- Post Office Protocol- Used to retrieve email from the server.- Most recent version of POP3.- Some email clients (eg Mozilla Thunderbird) will delete the email from the server after emails downloaded to the client workstation.- POP3 can not be used (not mesupport) mail delivery.
• IMAP- Internet Message Access Protocol- The protocol for accessing e-mails that exist on remote server- E-mail stays on the server- Users can access e-mail more than one client- IMAP is often used for remote file servers- The feature is similar to POP3 but more efficient and performance at a small bandwidth is better.
5. Method of Delivery
To send us electronic mail requires a mail-client program. Electronic mail that we send will go through several points before reaching the destination. For more details see the diagram below. The example used is a service SMTP (Simple Mail Transport Protocol) and POP3 (Post Office Protocol).
I write electronic mail → E-mail client (on my computer) → SMTP server of your e-mail me → Internet → POP3 e-mail provider's server → recipient e-mail client (the computer of the recipient) → read the letter of the recipient.
Visible electronic mail is sent only by 5 points (in addition to sending and receiving computers). Actually more than that because after leaving POP3 mail server then it will go through many other servers. There is a possibility that we send electronic mail intercepted others. Therefore when we send e-mails containing sensitive content should we take action to prevent, to randomize the (encrypted) data in electronic mail (eg using PGP, digital certificates, etc.).
6. Attacks Against Email
In the virtual world of an information security is not guaranteed. There are those who can do the theft or interception of the contents of electronic mail. Various attacks against the email can be done by parties who wish to obtain information from electronic mail. Example,s of attacks against the email is intercepted, forged, infiltrated (virus), spamming, mailbomb, mail relay.Below we will elaborate further about the type - the type of email attacks:
1. Tapping
E-mail such as postcards (postcards) that can be read by anyone. Where is the email sent by the MTA to "post office" to be forwarded to the nearest "post office" next until finally directed. That's why the potential of tapping can occur at any point of the pass.
2. Spoofing Mail (Counterfeiting)
Email forgery is made easy by making the preferred header. Where the fake email is then sent via MTA or directly via SMTP. However, activity was recorded in the server log file.
3. Infiltration (virus)
Email is often used as the most effective medium to spread the virus (via attachment), the contents of the email did not at first be examined by a firewall (because it's not a conventional firewall at the application layer), direct email to users who are often careless. Email clients directly execute programs based on file types acceptable for user convenience. This belief is at the misused by the virus.
4. Spamming
Spamming is sending an email to many people, usually used to do promotions (MLM, selling). Spamming can not be filtered by anti-virus.
7. Fake Login
Fake is fake page to login in. (login) to the account / page specific website, eg facebook, myspace, blogs etc.. Fake logins are often used by hackers to break into a specific password.
7. Securing Email Against Attacks
Security against email attacks we can do. Below will be explained more about the security of email attacks:
1. Safeguarding Against WiretappingUse encryption to scramble the contents of the letter. Examples of protection: PGP, GnuPG, PEM.
• PGP (Pretty Good Privacy)Pretty Good Privacy or PGP can be used to encrypt email or files. To ensure confidentiality, PGP uses public key cryptography. PGP also uses digital signatures to authenticate the identity of the sender, ensuring message integrity, and provides non-repudiation.
2. Against Spoofing Mail Security (Fraud)
Security of mail spoofing can be done by:
• See the header to find out the origin of the email.
• Using the digital signature
2. Against Spoofing Mail Security (Fraud)
Security of mail spoofing can be done by:
• See the header to find out the origin of the email.
• Using the digital signature
As for knowing the email fake or not it is necessary to analyze prior to the emails that we "guess" is. The steps that must not panic, read carefully the content of emails that we receive and try to check "Return-Path" email we receive. Here's how to do a return-path for mail-servers are widely used:
• YAHOO MAIL
- Classic, go first to the contents of the email and click the Full Headers (under the contents of the message)
- Modern, go first to the contents of the email and click the Actions tab and select Full Header
• GMAIL
- Basic (HTML), go first to the contents of the email and click the link Show Original
- Standard, go first to the contents of the email and click the down arrow button in the upper right corner (next to "reply) and select Show Original
Once we see the description of the "Return-path" from the email we receive, then we can know and make sure whether the emails are fake or not.
Once we see the description of the "Return-path" from the email we receive, then we can know and make sure whether the emails are fake or not.
3. Security Against Infiltration (virus)Security against intrusion (viruses) can be done by:
• Use anti-virus with the latest data.
• Do not allow your email client run the application.
• Perform a virus check on the mail server level.
4. Safeguarding Against Spamming
Spamming in Yahoo Mail can be prevented in the following way:
• Sign in to Yahoo! Mail.
• At the top left of the page, click Options | Mail Options.
• Click Spam from the list on the left.
• In the SpamGuard section, next to Control SpamGuard, there is a checkbox. If unchecked, then the active SpamGuard.
• the spam folder will be emptied once a month automatically In addition there are ways to cope with preventing and protecting email servers from spamming the victim is able to do some steps by the network administrator. As do the filtering and refusing spam include e-mail filtering based on the content of incoming email.
5. Safeguarding Against mailbomb
Safeguards against mailbomb can be done by:
• Limiting the size of the email.
• Quota disk (in the spool directory).
• Using special filters that detect duplicate content (content) email.
6. Safeguarding Against Fake Login
• Make a check to the URL of a login page, if properly derived from the original site.
CONCLUSION
From the discussion about email security, the authors conclude several points, including:
1. Email is the media sending a letter sent through the Internet, where security of the information is not guaranteed.
2. Many of the attacks against the email that can harm the user, but we can secure the appropriate type of email attacks.
3. Users are often careless can cause infiltration (virus) occurred, but it can be avoided by using anti-virus with the latest data.
4. In order to avoid fake login we have to check the URL of a login page, whether derived from the original site.
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