Posts Tagged: ransomware

Web Fraud 2.0 — 31 Comments
3
Jun 13

Cashout Service for Ransomware Scammers

There are 1,001 ways to swindle people online, but the hardest part for crooks is converting those ill-gotten gains into cash. A new service catering to purveyors of ransomware — malware that hijacks PCs until victims pay a ransom – levees a hefty fee for laundering funds from these scams, and it does so by abusing a legitimate Web site that allows betting on dog and horse races in the United States.

Ransonware scam spoofing the DHS to obtain Moneypak/unlock codes.

Ransonware scam spoofing the DHS to obtain Moneypak/unlock codes. Source: botnets.fr

Ransomware is most often distributed via hacked or malicious sites that exploit browser vulnerabilities.  Typically, these scams impersonate the Department of Homeland Security or the FBI (or the equivalent federal investigative authority in the victim’s country) and try to frighten people into paying fines to avoid prosecution for supposedly downloading child pornography and pirated content.

Ransomware locks the victim’s PC until he either pays the ransom or finds a way to remove the malware. Victims are instructed to pay the ransom by purchasing a prepaid MoneyPak card, sold at everything from Walgreens to Wal-Mart (some scams tell victims to pay using a PaySafe or Ukash card). Victims are then told to send the attackers a 14-digit voucher code that allows the bad guys to redeem those MoneyPak vouchers for cash.

Trouble is, taking funds off of a MoneyPak requires either spending it at stores that accept it, or hooking it up to a U.S. bank account, to PayPal, or to a prepaid Visa or Mastercard. What’s more, most miscreants who are even halfway competent at spreading ransomware can expect to collect dozens of MoneyPak codes per day, so cashing out via the above-mentioned methods simply does not scale well for successful bad guys (particularly those who live outside of the United States).

Last week, I stumbled on a ransomware cashout service hosted in Minsk, Belarus that helps simplify the process. It checks the balances of MoneyPak codes by abusing a feature built into betamerica.com, a legitimate and legal site where gamblers can go to bet on dog and horse races in the United States.  Specifically, the ransomware cashout service queries a page at betamerica.com that lets customers fund their betting accounts using MoneyPak.

I reached out to Betamerica.com’s operations team and spoke with a woman who would only give her name as “Leslie.” Leslie said the company had already flagged the account that was being used to check the MoneyPak voucher codes.

“This account was already flagged as some type of bot or compromise, and was set to non-wagering,” she said, explaining that this status prevents customer accounts from placing bets on races. Leslie said Betamerica scrutinizes the Moneypak activity because fraudsters have tried to use the codes to launder money.

“We are pretty diligent, because in the past we have had [individuals who] will try to do a Moneypak deposit and then do a withdrawal, basically trying to launder it. Bottom line is that money has to be wagered. It’s not going to be returned to you in another form.”

When I first encountered this ransomware cashout service and discovered the connection to Betamerica, I was sure the miscreants were trying to launder money through the betting site. But after my conversation with Leslie, the true scope of this ransomware operation began to come into focus. It appears to involve the cooperation of several sets of actors:

MoneyPak cashout scheme.

Scheme to cash out $300 MoneyPak vouchers obtained from ransomware victims.

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A Little Sunshine — 19 Comments
7
Jan 13

Crimeware Author Funds Exploit Buying Spree

The author of Blackhole, an exploit kit that booby-traps hacked Web sites to serve malware, has done so well for himself renting his creation to miscreants that the software has emerged as perhaps the most notorious and ubiquitous crimeware product in the Underweb. Recently, however, the author has begun buying up custom exploits to bundle into a far more closely-held and expensive exploit pack, one that appears to be fueling a wave of increasingly destructive online extortion schemes.

Cool Exploit Kit.

Cool Exploit Kit.

An exploit pack is a software toolkit that gets injected into hacked or malicious sites, allowing the attacker to foist a kitchen sink full of browser exploits on visitors. Those visiting such sites with outdated browser plugins may have malware silently installed. In early October  2012, security researchers began noticing that a new exploit pack called Cool Exploit Kit was showing up repeatedly in attacks from “ransomware,” malicious software that holds PCs hostage in a bid to extract money from users.

“Kafeine,” a French researcher and blogger who has been tracking the ties between ransomware gangs and exploit kits, detailed Cool’s novel use of a critical vulnerability in Windows (CVE-2011-3402) that was first discovered earlier in the year in the Duqu computer worm. Duqu is thought to be related to Stuxnet, a sophisticated cyber weapon that experts believe was designed to sabotage Iran’s nuclear program.

About a week after Kafeine highlighted the Duqu exploit’s use in Cool, the same exploit showed up in Blackhole. As Kafeine documented in another blog post, he witnessed the same thing happen in mid-November after he wrote about a never-before-seen exploit developed for a Java vulnerability (CVE-2012-5076) that Oracle patched in October. Kafeine said this pattern prompted him to guess that Blackhole and Cool were the work of the same author or malware team.

“It seems that as soon as it is publicly known [that Cool Exploit Kit] is using a new exploit, that exploit shows up in Blackhole,” Kafeine said in an interview with KrebsOnSecurity.

As detailed in an excellent analysis by security firm Sophos, Blackhole is typically rented to miscreants who pay for the use of the hosted exploit kit for some period of time. A three-month license to use Blackhole runs $700, while a year-long license costs $1,500. Blackhole customers also can take advantage of a hosting solution provided by the exploit kit’s proprietors, which runs $200 a week or $500 per month.

Blackhole is the brainchild of a crimeware gang run by a miscreant who uses the nickname “Paunch.” Reached via instant message, Paunch acknowledged being responsible for the Cool kit, and said his new exploit framework costs a whopping $10,000 a month.

At first I thought Paunch might be pulling my leg, but that price tag was confirmed in a discussion by members of a very exclusive underground forum. Not long after Kafeine first wrote about Cool Exploit Kit, an associate of Paunch posted a message to a semi-private cybercrime forum, announcing that his team had been given an initial budget of $100,000 to buy unique Web browser exploits, as well as information on unpatched software flaws. Here is a portion of that post, professionally translated from Russian:

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A Little Sunshine / The Coming Storm / Web Fraud 2.0 — 46 Comments
13
Aug 12

Inside a ‘Reveton’ Ransomware Operation

The U.S Federal Bureau of Investigation is warning about an uptick in online extortion scams that impersonate the FBI and frighten people into paying fines to avoid prosecution for supposedly downloading child pornography and pirated content. This post offers an inside look at one malware gang responsible for orchestrating such scams.

Reveton ransomware scam impersonating FBI

Reveton ransomware scam page impersonating the FBI

In an alert published last week, the FBI said that The Internet Crime Complaint Center — a partnership between the FBI and the National White Collar Crime Center — was “getting inundated with complaints” from consumers targeted or victimized by the scam, which uses drive-by downloads to hijack host machines. The downloaded malware displays a threatening message (see image to the right) and blocks the user from doing anything else unless he pays the fine or finds a way to remove the program.

The FBI alert said the attacks have surged with the help of a “new drive-by virus” called Reveton; in fact, Reveton and its ilk are hardly new. These types of attacks have been around for years, but traditionally have targeted European users. The scam pages used in the attacks mimic official notices from various national police or investigatory agencies, corresponding to the country in which the victim resides. For a breakdown of these Reveton-related ransomware scam pages by country, see this comprehensive gallery set up at botnets.fr.

Reveton.A is blamed in these most recent attacks, and the FBI said it appears Reveton is being distributed in conjunction with Citadel, an offshoot of the ZeuS Trojan that I have written about on several occasions. It is certainly possible that crooks are using Citadel to deploy Reveton, but as I’ll illustrate below, it seems more likely that the attackers in these cases are using exploit kits like BlackHole to plant both threats on victim PCs.

INSIDE A REVETON MALWARE GANG

Operations of one Reveton crime group. Source: ‘Kafeine,’ from botnets.fr.

At least that’s the behavior that’s been observed by a ragtag group of researchers that has been tracking Reveton activity for many months. Some of the researchers are associated with botnets.fr, but they’ve asked to remain nameless because of the sensitivity of their work. One of them, who goes by the screen name “Kafeine,” said much of the Reveton activity traces back to a group that is controlling the operation using reverse proxies at dozens of servers scattered across data centers globally (see this PDF for a more detailed look at the image above).

Kafeine said the groups involved in spreading Reveton are constantly fine-tuning all aspects of their operations, from the scam pages to solidifying their back-end hosting infrastructure. The latest versions of Reveton, for example, serve the scam pages from an encrypted (https://) connection, and only cough up the pages when an infected machine visits and sends a special request. Continue reading →

A Little Sunshine — 25 Comments
17
Oct 11

Software Pirate Cracks Cybercriminal Wares

Make enough friends in the Internet security community and it becomes clear that many of the folks involved in defending computers and networks against malicious hackers got started in security by engaging in online illegal activity of one sort or another. These gradual mindset shifts are sometimes motivated by ethical, karmic or personal safety reasons, but just as often grey- and black hat hackers gravitate toward the defensive side simply because it is more intellectually challenging.

I first encountered 20-year-old French hacker Steven K. a few months ago while working on a series about the fake antivirus industry. I spent several hours reading accounts of his efforts to frustrate and highlight cybercriminal activity, and took time to follow the many links on his blog, XyliBox, a variant of his hacker alias, “Xylitol.” It turns out that Xylitol, currently unemployed and living with his parents, is something of a major player in the software piracy or “warez” scene, which seeks to crack the copy protection technology built into many computer games and commercial software programs.

As a founding member of redcrew.astalavista.ms (this site may be flagged by some antivirus software as malicious), Xylitol spent several years devising and releasing “cracks,” software patches that allow people to use popular commercial software titles without paying for a license. Cracks are frequently bundled with backdoors, Trojans and other nasties, but Xylitol claims his group never tainted its releases; he says this malicious activity is most often carried out by those who re-purpose and redistribute the pristine patches for their own (commercial and criminal) uses.

But about a year ago, Xylitol began shifting his focus to reverse engineering malware creation kits being marketed and sold on underground cybercrime forums. In October 2010, he began releasing cracked copies of the the bot builder for the SpyEye Trojan, a crimeware kit that sells for several thousand dollars. Each time the SpyEye author released an update, Xylitol would crack it and re-release a free version. This continued for at least a dozen updates in the past year.

The cracked SpyEye releases have been met with a mix of praise and scorn from the security industry; the free releases no doubt frustrated the moneymaking capabilities of the SpyEye author, but they also led to the public distribution of a malware kit that had previously been much harder to come by.

In an instant message chat, Xylitol said he still cracks the occasional commercial software title, just for old time’s sake.

“Sometimes for the old memories, but I’m more into malware cracking now,” he wrote. “It’s more fun.”

Since Nov. 2010, Xylitol and some of his associates have been locked in a daily battle with Russian scareware and ransomware gangs. Scareware programs hijack PCs with incessant and misleading security warnings in a bid to frighten users into paying for the worthless software. Paying customers are given a license key eliminates the annoying security warnings. Ransomware is even more devious: It encrypts the victim’s personal files — pictures, documents, movies and music files — with a custom encryption key. Victims who want their files back usually have little recourse but to pay a fee via text message to receive a code that unlocks the encrypted files.

Xylitol and his pals have been busy over the past year cracking and publishing the license keys needed to free computers snared by scareware and ransomware. For months, these guys have been taking on a Russian ransomeware group called the WinAd gang, releasing the ransomware codes on a daily basis, often just hours after the WinAd gang began pushing out new ransomware variants.

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