Scareware | The IT Security Attaché

Busted! Conficker’s tell-tale heart uncovered. Researchers find super worm cure, just in time – Yaayy

March 31, 2009 at 1:15 pm Brett A. Scudder No comments

Original URL: http://www.channelregister.co.uk/2009/03/30/conficker_signature_discovery/

Busted! Conficker’s tell-tale heart uncovered

Researchers find super worm cure, just in time

Posted in Software & Security, 30th March 2009 11:02 GMT

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Security experts have made a breakthrough in their five-month battle against the Conficker worm, with the discovery that the malware leaves a fingerprint on infected machines that is easy to detect using a variety of off-the-shelf network scanners.

The finding means that, for the first time, administrators around the world have easy-to-use tools to positively identify machines on their networks that are contaminated by the worm. As of mid-Monday, signatures will be available for at least half a dozen network scanning programs, including the open-source Nmap (http://nmap.org/), McAfee’s Foundstone Enterprise (http://www.mcafee.com/us/enterprise/products/risk_management/foundstone_enterprise.html) and Nessus (http://www.nessus.org/nessus/), made by Tenable Network Security.

Up to now there were only two ways to detect Conficker, and neither was easy. One was to monitor outbound connections for each computer on a network, an effort that had already proved difficult for organizations with machines that count into the hundreds of thousands or millions. With the advent of the Conficker C variant (http://www.theregister.co.uk/2009/03/07/conficker_upgrade/), traffic monitoring became a fruitless endeavour because the malware has been programmed to remain dormant until April 1.

The only other method for identifying Conficker-infected computers was to individually scan each one, another measure that placed onerous requirements on admins.

The discovery of Conficker’s tell-tale heart two days before activation may prove to be an ace up the sleeve of the the white hat security world.

“This is an extraordinarily inexpensive, not-very-time-intensive way of finding machines on your network that are actually running malicious software,” said Dan Kaminsky, one of the three researchers who discovered the Conficker fingerprint. “This is not something we get to do all the time. Most pieces of malicious software are not that easy to find.”

The availability of the new Conficker definitions is the result of the sleuthing and quick response of an industry-wide cast of characters, said Kaminsky, who is director of penetration testing at security company IOActive (http://ioactive.com/).

The finding came Friday afternoon as Kaminsky pored over data that members of the Honeynet Project (http://www.honeynet.org/) had collected on the worm. Along with Honeynet’s Tillmann Werner and Felix Leder, Kaminsky soon noticed that Conficker changes the way a small piece of the Windows operating system acts. The behavior, located in pre-authentication routines before users enter file-sharing passwords, makes easy-to-identify changes to the way machines look on a network.

“Once I heard that Conficker had code running on the anonymous surface, I said ‘Wait, we can fingerprint that,’” Kaminsky said. “If you can get packets to a box, you can find out fairly reliably whether it’s infected with Conficker.”

Kaminsky said he then turned to help from Securosis researcher Rich Mogull, who on Saturday began mobilizing providers of network scanning products to add the Conficker definitions as soon as possible.

“This is the fastest turn-around I’ve ever seen,” Kaminsky said.

Products from Qualys and ncircle are also expected to add anti-Conficker detection signatures. Werner and Leder have developed their own proof-of-concept scanner, which is available here (http://iv.cs.uni-bonn.de/uploads/media/scs.zip).

Since showing up a few days after Microsoft released an emergency patch (http://www.theregister.co.uk/2008/10/23/emergency_windows_update/) for Windows in late October, Conficker has elicited a grudging admiration from security professionals, who can’t help acknowledging the worm’s sophistication. It attacked multiple vectors, was able to crack passwords and spread like wildfire, infecting more than ten million boxes in just a few months’ time, by some estimates.

Conficker’s profile has only grown larger in the past few weeks as the calendar slowly approaches April 1. That’s the day that machines infected with Conficker C will be able to tap into a much larger pool of internet addresses to receive instructions – 50,000 instead of the previous 250.

But it would appear the evil geniuses who spawned the malware made a fatal error that until now had gone unnoticed. Its discovery just a few days before an important deadline could lead to its eradication – but only if network admins worldwide put down what they’re doing and make use of the tools now.

“We have no idea what Conficker is going to do on April 1,” Kaminsky said. “Certainly there is no reason anyone wants to find out on their network. My recommendation is that people run one of the vulnerability scanners on Monday or Tuesday.” ®

Related stories

· Scareware scammers latch onto Conficker hype (31 March 2009)

· Leaked memo says Conficker pwns Parliament (27 March 2009)

· Final countdown to Conficker ‘activation’ begins (26 March 2009)

· Scottish hospitals laid low by malware infection (9 March 2009)

· Conficker gets upgraded with defenses (7 March 2009)

· Conficker variant dispenses with need to phone home (23 February 2009)

· MS puts up $250K bounty for Conficker author (12 February 2009)

· Countdown to Conficker activation begins (23 January 2009)

· Superworm seizes 9m PCs, ’stunned’ researchers say (16 January 2009)

IT Security Alerts, Notices and Advisories Busted, Conficker Cure, Experts, IOActive, nCircle, proof-of-concept scanner, Qualys, Scareware

New ransomware holds Windows files hostage, demands $50

March 26, 2009 at 4:17 pm Brett A. Scudder No comments

New ransomware holds Windows files hostage, demands $50
‘Sobering’ turn by crooks ‘doesn’t bode well,’ says researcher
Gregg Keizer

http://www.computerworld.com/action/article.do?command=viewArticleBasic&articleId=9130539&source=NLT_AM

March 25, 2009 (Computerworld) Cybercrooks have hit on a new twist to their aggressive marketing of fake security software and are duping users into downloading a file utility that holds users’ data for ransom, security researchers warned today.

While so-called scareware has plagued computer users for months, those campaigns have relied on phony antivirus products that pretend to trap malware but actually only exist to pester people into ponying up as much as $50 to stop the bogus warnings.

The new scam takes a different tack: It uses a Trojan horse that’s seeded by tricking users into running a file that poses as something legitimate like a software update. Once on the victim’s PC, the malware swings into action, encrypting a wide variety of document types — ranging from Microsoft Word .doc files to Adobe Reader PDFs — anytime one is opened. It also scrambles the files in Windows’ “My Documents” folder.

When a user tries to open one of the encrypted files, an alert pops up saying that a utility called FileFix Pro 2009 will unscramble the data. The message poses as an semiofficial notice from the operating system. “Windows detected that some of your MS Office and media files are corrupted. Click here to download and install recommended file repair application,” the message reads.

Clicking on the alert downloads and installs FileFix Pro, but the utility is anything but legit. It will decrypt only one of the corrupted files for free, then demands the user purchase the software. Price? $50.

“This does look like a new tactic,” said David Perry, the global director of education at antivirus vendor Trend Micro Inc. “But all online fraud is just minor variations of classic con games. This is just the ‘Bank Examiner’ played out on the Internet.”

That classic con, said Perry, typically involves a swindler posing as an official, a bank examiner or an FBI agent who asks for help in an investigation. The swindler convinces the mark to withdraw money from the bank — it’s needed to catch the nonexistent crook in the act — and promises to return the funds at the end of the case. Of course, the money vanishes, along with the grifter.

On the Web, data-hostage scams like this are called “ransomware” for obvious reasons. This isn’t the first time the tactic has been used, but it is remarkably polished, said Perry. “We’ve not seen ransomware with this level of sophistication,” he said.

Users who have fallen for the FileFix Pro 2009 con do not have to fork over cash to restore their files, according to other researchers, who have figured out how to decrypt the data. The Bleeping Computer site, for instance, has a free program called “Anti FileFix” available for download that unscrambles files corrupted by the Trojan horse. And security company FireEye Inc. has created a free online decrypter that also returns files to their original condition.

Alex Lanstein, a malware researcher at FireEye who blogged about FileFix Pro 2009 last week, called the turn from scareware to ransomware “sobering.”

“Although we broke the encryption, it’s a sobering realization of the state of malware that it is now actively extorting users by holding their data ransom,” Lanstein said. “Despite this version of FileFix being trivial to crack, it does not bode well for the future of Internet malware.”

If ransomware follows a similar path as scareware, criminals will be hustling to mimic FileFix Pro. According to some estimates, crooks make as much as $5 million a year pushing fake antivirus software.