spam

Sep 24 2008   1:12AM GMT

Software for Secure Computing: Trend Micro’s RUBotted

Posted by: Ken Harthun
Anti-malware, Botnet, IRC bot, spam, Secure Computing, Virus

I stumbled across this nifty free tool when running an online scan at Trend Micro’s HouseCall site. Botnets are a big problem, accounting for most of the spam on the Internet, not to mention their use in stealing financial information and launching denial-of-service (DoS) attacks. RUBotted (Beta) “…monitors your computer for suspicious activities and regularly checks with an online service to identify behavior associated with Bots. Upon discovering a potential infection, RUBotted prompts you to scan and clean your computer.” Note that this tool doesn’t clean anything–you still have to use antivirus software. Alternatively, you can take advantage of one of the many online malware scanners.

The tool runs on Windows 2000, Windows XP Home and Professional, Windows 2003 Server, and Windows Vista (32-bit only), providing the latest service packs are installed. There’s one caveat, however:  Trend says, “RUBotted cannot protect computers running Panda Internet Security 2008.”

I hope that this effort by Trend starts a trend (pun intended) of vendors providing similar secure computing software, perhaps incorporating bot removal tools to boot. We’ll see.

Aug 23 2008   2:39AM GMT

Oscarbot.UG Eludes Detection with Intelligent Stealth

Posted by: Ken Harthun
Cybercrime, Anti-malware, Anti-virus, spam, Malware, Phishing, Opinion, Virus

According to Panda Security, the Oscarbot.UG virus, first detected on August 17, 2008, uses intelligent stealth techniques to avoid detection.  “It deletes the original file from which it was run once it is installed on the computer. It uses several methods in order to avoid detection by antivirus companies [one of them being that it] terminates its own execution if it detects that it is being executed in a virtual machine environment, such as VMWare or VirtualPC.”

As reported by Help Net Security, the worm “stops running if it finds that it is being tried on virtual machines such as vmware, a sandbox or in a honeypot (these tools are often used to check in a controlled environment if an executable file is running malicious commands).

The good news is that anyone running a virtual environment is safe from infection: The worm won’t run and when you shut down the virtual machine, it’s gone. The bad news is that malware using this type of intelligent stealth is on the rise, raising the bar for anti-malware researchers.

At what point do we switch from a reactive anti-malware approach (blacklisting) to a pro-active one (whitelisting)? The day is fast approaching (it may already be here) when the programs designed to protect us become so huge and so invasive that they prevent us from getting any useful work done.

The best way to combat malware would be to take the profit out of spam, phishing scams, and other cyber-fraud crimes.

I don’t have the answer for that one.

Aug 11 2008   3:42PM GMT

The Best Way to Avoid Spam

Posted by: Ken Harthun
Security, email, spam, Secure Computing

In the 1986 hit movie, The Karate Kid - Part II, the kid’s instructor, Mr. Miyagi, uttered this famous line: “Best way to avoid punch, no be there!” Good advice, indeed; it’s one of those universal pieces of truth that’s so obvious, it’s overlooked. The beauty of it is that it can be applied to anything. In this case, I’ll apply it to spam email, the electronic equivalent of a punch: “Best way to avoid spam, no have email address!”

That’s not exactly practical; we all have an email address. Some of us have several of them (at last count, I have at least nine addresses and I’m sure I’ve missed a couple somewhere). In my final installment of the “How to Secure Your Computer” series, “If Spam has You Irate, Obfuscate!” I gave examples of how you can make your email address unreadable by web bots. Well, that can be a bit of work, forcing you to cut and paste, and make other efforts that can quickly become tedious. There’s an easier way.

Enter Mailinator, the completely anonymous email address that you create on-the-fly when you need to enter an email address but don’t want to use your real one. From their site:

How do I create an account at Mailinator? It’s simple, you just send email to it. Temporary accounts are created when email arrives for them. First, you give out the mailinator email address you created, and then you check it. It’s that simple.

Do I have to sign up? No sign-up, you don’t even have to tell Mailinator you’re coming.

It’s a valid, working email address that you can check just by visiting the site. Of course, anyone can check it just by entering the address in the “Check your inbox” box. Not the best of situations, so they fixed it by providing alternate inbox names . In a nutshell, you use the alternate inbox name for your email address when you post it publicly. Anyone who enters the alternate inbox name will simply get a “no messages” message. Pretty slick.

The beauty of Mailinator is that it provides a valid email address; you can download stuff from and subscribe to those sites that require clicking links in confirmation emails without having to worry about exposing yourself to spam. Use the alternate inbox name or even a different email address every time you need one.

Best way to avoid spam, no have email address — or at least use one you can throw away at will. Either way, you avoid the punch and the security risk.

Jul 27 2008   4:09PM GMT

Nine Steps to System Security - 2008

Posted by: Ken Harthun
Security, Anti-malware, Anti-virus, Firewalls, Malware, Phishing, Vulnerabilities, Email security, spam, Microsoft Windows, Browsers, NAT, Routers, Opinion, Rootkit

It isn’t getting any better on The Wild, Wild Web, despite state and federal government attempts to arrest and prosecute those responsible for electronically-perpetrated criminal acts. Spyware and malware of all kinds are increasingly more stealthy and difficult to remove thanks to rootkit technology. With the advent of Web 2.0 and its emphasis on sharing and collaboration, web-based attacks are more prevalent than ever, especially those that rely on JavaScript and other scripting languages.

CAN-SPAM did little to deter or eliminate spammers, and today the spam problem is even worse thanks to huge botnets run by organized cyber-crime syndicates. Phishing attacks are harder to detect and more frequent. Recently, I spent the better part of two days cleaning up the aftermath of a mass mailer worm infection for one of our clients; their email is still being blocked by some servers. In its September 2005 issue, Consumer Reports said, “One Third Of Net Users Damaged By Malware.” Considering that article is three years old, I’d wager that the number of infected computers has doubled since then.

In my job as a systems engineer for Connective Computing, Inc., I deal with the effects of malware nearly every day. My previous releases of this article, Seven Steps to System Security - 2004 and Seven Steps to System Security - 2005, and Eight Steps to System Security – 2005, listed the field-proven steps I recommend to everyone I know. It’s been nearly three years since I published my latest version, but those eight steps haven’t changed much; they just need to be brought up to date, and a new step involving disabling scripting in the browser has been added. Computer users still haven’t learned safe surfing practices, however (will they ever?), and must modify their on-line behavior–particularly by applying the first step–for rest of these steps to be truly effective.

Did I mention these things are proven? They are. These are practices have been protecting computer users in homes and businesses for as long as I’ve been using them. This is free advice that’s really worth something:

1. Repeat after me: I will NEVER, EVER click on any pop-up of any kind - NEVER, EVER. Not even on the “X” (it’s usually safe, but why take the chance?). Use the key combination Alt-F4 instead; it safely closes the current window. In the slimy world of sleaze-ware, “No” means yes, “Cancel” means yes, “Close” means yes - ANY click on a button means yes. So many times users ask, “How did I get that? I clicked ‘no’ when it asked me!” Well, sorry, but you clicked, so they got you. NEVER, EVER CLICK!
2. Although Internet Explorer 7.0 has enhanced security and has been detached somewhat from the Windows operating system, it is still too big a target. Crackers are still writing malware that exploits IE security flaws. I recommend you use Firefox or Opera to browse the Web. (Some web sites still require IE, so you’ll be forced to use it for those, but you should minimize its use otherwise.) Whatever browser you use, be sure you configure your preferences to block all unwanted pop-ups or install a pop-up killer like the Google Tool Bar. And while you’re at it, re-read #1!
3. Patch your system. If you’re still running XP, make sure you have at least service pack 2. If you’re a home user, install service pack 3. (I still see systems that are running XP with service pack 1 or 1a, probably because they turned off automatic updates. While some argue against it, I recommend you turn them on.) And be sure to install any recommended security updates and patches for ALL software on your system, - especially Microsoft Office - not just Windows. If you’re running Windows Vista, you benefit from its enhanced security, but you still need to keep ALL of your applications patched. Secunia’s Online Software Inspector is an excellent tool for scanning your system’s applications to discover those that need updates.
4. Besides installing a NAT router (see How to Secure Your Computer: Maxim #2), run a properly-configured, proven software firewall. Don’t rely only on Windows XP’s built-in firewall - it blocks inbound attacks only (see this article) and it has flaws of its own (see this article). It will not stop back-door trojans, adware, spyware, and the like from “phoning home” with your sensitive information. (See this article for more info.) While Vista’s firewall does offer outbound filtering, it isn’t much better (see this article for more information). My favorites are the Comodo Personal Firewall (free), and the Sunbelt Kerio Personal Firewall (full-featured for 30 days, then runs free in limited-feature mode, $19.95/yr for full version).
5. Run a good anti-virus program. Choices abound. I have used AntiVir Personal Edition (free) and Grisoft’s AVG (free). Other good ones are Avast! and Comodo AntiVirus.
6. Run multiple anti-spyware/anti-adware programs and keep them updated. I recommend: a. Spyware Blaster. This free program blocks adware and spyware from installing in the first place and is frequently updated; b. Ad-Aware. Scan weekly, more frequently if you are a heavy surfer; c. Spybot S&D. Run it on the same schedule as Ad-Aware; d. Microsoft’s Windows Defender is an excellent product and is installed by default in Windows Vista. Configure it for real time protection and automatic updates. One of the best commercial anti-spyware applications is Sunbelt Software’s CounterSpy. It is a PC World Best Buy award winner. Comodo BOClean:AntiMalware is also a good one and it’s free.
7. Run a spam blocker to isolate junk e-mail. Most malware and all phishing attempts rely on spam. You want to isolate this stuff and delete it. NEVER, I repeat, NEVER, EVER click on a link in any e-mail you are not absolutely certain is legitimate. And to be as safe as possible, always type in the address of your bank, credit card companies, and any other site that you want to keep secure. (See #1 above and apply that principle to links, too!) One of the best programs is Open Field Software’s ella for Spam Control. It uses wizards to “train” it to your personal specifications. There are free and paid versions that work with Outlook, Outlook Express. My clients swear by it. Another good program is Sunbelt Software’s iHate Spam.
8. On Windows XP, set up a restricted user account and use that for routine tasks. Only log on with administrative privileges when you need to install or configure software. This will prevent rogue programs from affecting your system - they won’t be able to install. You can activate the “run as” feature so you can do administrative tasks while logged in as a restricted user. Microsoft Knowledge Base article Q294676 explains how to activate and use this feature. If you are running Vista, you don’t have to worry about this step: User Access Control (UAC) takes care of it.
9. Finally, disable scripting in your browser. If you use IE (you probably shouldn’t, see Step 2), Tony Bradley gives you an excellent step-by-step procedure to accomplish this. Firefox users have a more elegant solution in the form of an add-on: NoScript. I use it on every PC. Scripts are blocked globally by default, but you can selectively activate them if you trust the site. For example, you can trust the main site’s scripts but keep blocking any advertising or other third party scripts with no ill effects.

While total immunity is impossible - new infections and variations on existing exploits appear daily - these nine steps will help prevent, catch, or clean 98 percent of the junkware out there. As for the other two percent - or if you are already badly infected - you’ll need to hire a geek like me.

Jul 25 2008   1:45AM GMT

Sure-fire Spam Zombie Killer

Posted by: Ken Harthun
Exchange, email, Email security, spam, Networking, Routers, Security, Firewalls

The other day, I got a call from one of my clients who said that their email was bouncing back from people they had always been able to send to. I investigated and found that the error message was to the effect of <hostname.domain #5.5.0 smtp;550 Blocked;Spam/Zombie address listed at spamhaus.org sbl-xbl>.

Well, that was odd, because the client is running a bona fide Exchange server and a check of the server revealed nothing wrong that I could see. Thinking that maybe an employee was infected with a mass-mailer trojan, I blocked all traffic on smtp port 25 from all addresses on the network except the Exchange server.

Running the netstat -an command on my client’s PC revealed 88 connections, all trying to send mail out on port 25, which the firewall was now blocking.

Certainly, you don’t want to get infected by a mass-mailer trojan, but blocking outbound traffic on port 25 from your network is a sure-fire spam zombie killer and will prevent your IP address from getting blacklisted if someone does get infected.Of course, you’ll want to clean up that infection as quickly as possible.

May 29 2008   5:14PM GMT

Beware the Internet Criminals’ Latest Trick

Posted by: Ken Harthun
Security, spam, Phishing, Email security, Browsers, Opinion

Some spammers, phishers, and other Internet criminals have resorted to (mis)using the convenient service of tinyurl.com in order to disguise their web site addresses and entice you into clicking. Tinyurl.com takes those weird, long URLs and converts them into something smaller and more manageable. So, instead of a URL that might look like this, http://3468664375@3468664375/o%62s%63ur%65%2e%66t%6D (not a real address), you see one that looks like this: http://tinyurl.com/d99g5. That’s a bit less intimidating and you may be tempted to click on it. Don’t; you’ll be sorry.

Never, ever click on a link in an email unless you know and trust the sender. Never, ever click on a link in a website, blog post, online article, or what-have-you, unless you know the content is safe.