From Spam Daily News’s “Spam zombies from outer space“:
Spammers could soon use zombie computers in a totally new way. Infected computers could run programs that spy into a person’s email, mine it for information, and generate realistic-looking replies.
John Aycock, an assistant professor of computer science at the University of Calgary, and his student Nathan Friess conducted new research that shows it is possible to create a new type of spam that would likely bypass even the best spam filters and trick experienced computer users who would normally delete suspicious email messages.
There are two key reasons why spam is suspicious to anti-spam filters and human targets alike. First, it often comes from an unrecognized source. Second, it doesn’t look right.
The evolution of spam zombies will change this. These new zombies will mine corpora of email they find on infected machines, using this data to automatically forge and send improved, convincing spam to others.
The next generation of spam could be sent from your friends’ and colleagues’ email addresses – and even mimic patterns that mark their messages as their own (such as common abbreviations, misspellings, capitalization, and personal signatures) – making you more likely to click on a Web link or open an attachment.
What features can be easily extracted from an email corpus? There are four categories:
1. Email addresses. The victim’s email address and any other email aliases they have can be extracted, as can the email addresses of people with whom the victim corresponds.
2. Information related to the victim’s email program and its configuration. For example, the User-Agent, the message encoding as text and/or HTML, automatically-appended signature file, the quoting style used for replies and forwarded messages, etc.
3. Vocabulary. The normal vocabulary used by the victim and the people with whom they correspond.
4. Email style.
- Line length, as some people never break lines;
- Capitalization, or lack thereof;
- Manually-added signatures, often the victim’s name;
- Abbreviations, e.g., “u” for “you”;
- Misspellings and typos;
- Inappropriate synonyms, e.g., “there” instead of “their”;
- Replying above or below quoted text in replies.