Posts Tagged: FireEye


6
Aug 14

New Site Recovers Files Locked by Cryptolocker Ransomware

Until today, Microsoft Windows users who’ve been unfortunate enough to have the personal files on their computer encrypted and held for ransom by a nasty strain of malware called CryptoLocker have been faced with a tough choice: Pay cybercrooks a ransom of a few hundred to several thousand dollars to unlock the files, or kiss those files goodbye forever. That changed this morning, when two security firms teamed up to launch a free new online service that can help victims unlock and recover files scrambled by the malware.

clssFirst spotted in September 2013, CryptoLocker is a prolific and very damaging strain of malware that uses strong encryption to lock files that are likely to be the most valued by victim users, including Microsoft Office documents, photos, and MP3 files.

Infected machines typically display a warning that the victim’s files have been locked and can only be decrypted by sending a certain fraction or number of Bitcoins to a decryption service run by the perpetrators. Victims are given 72 hours to pay the ransom — typically a few hundred dollars worth of Bitcoins — after which time the ransom demand increases fivefold or more.

But early Wednesday morning, two security firms – Milpitas, Calf. based FireEye and Fox-IT in the Netherlands — launched decryptcryptolocker.com, a site that victims can use to recover their files. Victims need to provide an email address and upload just one of the encrypted files from their computer, and the service will email a link that victims can use to download a recovery program to decrypt all of their scrambled files.

The free decryption service was made possible because Fox-IT was somehow able to recover the private keys that the cybercriminals who were running the CryptoLocker scam used on their own (not free) decryption service. Neither company is disclosing much about how exactly those keys were recovered other than to say that the opportunity arose as the crooks were attempting to recover from Operation Tovar, an international effort in June that sought to dismantle the infrastructure that CryptoLocker used to infect PCs.

Continue reading →


27
Apr 14

Microsoft Warns of Attacks on IE Zero-Day

Microsoft is warning Internet Explorer users about active attacks that attempt to exploit a previously unknown security flaw in every supported version of IE. The vulnerability could be used to silently install malicious software without any help from users, save for perhaps merely browsing to a hacked or malicious site.

In an alert posted on Saturday, Microsoft said it is aware of  “limited, targeted attacks” against the vulnerability (CVE-2014-1776) so far.

Microsoft’s security advisory credits security firm FireEye with discovering the attack. In its own advisory, FireEye says the exploit currently is targeting IE9 through IE11 (although the weakness also is present in all earlier versions of IE going back to IE6), and that it leverages a well-known Flash exploitation technique to bypass security protections on Windows.

ie0daymitigationMicrosoft has not yet issued a stopgap “Fix-It” solution for this vulnerability. For now, it is urging IE users to download and install its Enhanced Mitigation Experience Toolkit (EMET), a free tool that can help beef up security on Windows. Microsoft notes that EMET 3.0 doesn’t mitigate this attack, and that affected users should instead rely on EMET 4.1. I’ve reviewed the basics of EMET here. The latest versions of EMET are available here.

According to information shared by FireEye, the exploit also can be blocked by running Internet Explorer in “Enhanced Protected Mode” configuration and 64-bit process mode, which is available for IE10 and IE11 in the Internet Options settings as shown in the graphic above.

This is the first of many zero-day attacks and vulnerabilities that will never be fixed for Windows XP users. Microsoft last month shipped its final set of updates for XP. Unfortunately, many of the exploit mitigation techniques that EMET brings do not work in XP.


1
Mar 13

New Java 0-Day Attack Echoes Bit9 Breach

Once again, attackers are leveraging a previously unknown critical security hole in Java to break into targeted computers. Interestingly, the malware and networks used in this latest attack match those found in the recently disclosed breach at security firm Bit9.

The discovery of the Java zero-day is being co-credited to FireEye and CyberESI, two companies that specialize in tracking cyber espionage attacks. In its writeup, FireEye said multiple customers had been attacked using a newly-found flaw in the latest versions of Java — Java 6 Update 41, and Java 7 Update 15.

FireEye said the Java exploit used in this attack downloaded a remote access Trojan called McRat. This threat, also known as HiKit and Mdmbot.F, calls home to a malicious control server at the Internet address 110.173.55.187. Turns out, this is the same malware and control server that was used in the attack on Bit9, according to details that Bit9 released in a blog post this week documenting a sophisticated attack that resulted in a breach of its own systems last year.

Alex Lanstein, a senior security researcher at FireEye, said it’s unlikely in this case that multiple attack groups are using the same infrastructure and malware.

“Same malware, same [command and control server], I’d have to say it’s the same group that hit Bit9,” Lanstein said.

Continue reading →


28
Dec 12

Attackers Target Internet Explorer Zero-Day Flaw

Attackers are breaking into Microsoft Windows computers using a newly discovered vulnerability in Internet Explorer, security experts warn. While the flaw appears to have been used mainly in targeted attacks so far, this vulnerability could become more widely exploited if incorporated into commercial crimeware kits sold in the underground.

IEwarningIn a blog posting Friday evening, Milpitas, Calif. based security vendor FireEye said it found that the Web site for the Council on Foreign Relations was compromised and rigged to exploit a previously undocumented flaw in IE8 to install malicious software on vulnerable PCs used to browse the site.

According to FireEye, the attack uses Adobe Flash to exploit a vulnerability in the latest (fully-patched) version of IE8. Dustin Childs, group manager for response communications at Microsoft, said the vulnerability appears to exist in previous versions of IE.

“We are actively investigating reports of a small, targeted issue affecting Internet Explorer 6-8,” Childs said in an emailed statement. “We will take appropriate action to help keep customers protected once our analysis is complete. People using Internet Explorer 9-10 are not impacted.”

As FireEye notes, this is another example of a “watering hole” attack, which involves the targeted compromise of legitimate websites thought to be of interest to or frequented by end users who belong to organizations that attackers wish to infiltrate. Earlier this year, I wrote about similar zero-day attacks against visitors to the Web sites of the National Democratic Institute, The Carter Center, and Radio Free Europe.

Update, Dec. 30, 9:25 a.m. ET: Microsoft has officially acknowledged this vulnerability in an advisory, which contains some advice for IE users about how to mitigate the threat. As IE versions 9 and 10 are not impacted, users running Windows Vista or higher can upgrade to the latest browser version here.

Update, Jan.1 8:56 p.m. ET: Microsoft’s advisory now includes a link to a stopgap “FixIt” solution that may help to blunt attacks until the company issues an official patch for this vulnerability.


10
Dec 12

Espionage Attacks Against Ruskies?

Hardly a week goes by without news of a cyber espionage attack emanating from China that is focused on extracting sensitive data from corporations and research centers in the United States. But analysis of a recent malware campaign suggests that cyberspies in that region may be just as interested in siphoning secrets from Russian targets.

The Cyrillic text used in the decoy document.

Researchers at Milpitas, Calif. based security firm FireEye say they spotted an email attack of apparent Chinese origin that used Russian language lures to steal data from mostly Russian victims. The email malware campaign embedded a Microsoft Word exploit that displayed a decoy document containing news about a meeting of ASEAN, the Association of Southeast Asian Nations.

According to FireEye’s Alex Lanstein, this campaign had its control infrastructure in Korea and Japan, but clues point to Chinese design and operation. The malicious Word document sample that kicked this off was authored from a Microsoft Windows system that was set to use the language pack “Windows Simplified Chinese (PRC, Singapore). The researchers also say they were able to gain access to the control server used in the attack, which revealed systems logging in from China to check on new victims.

Update, 1:05 p.m. ET: FireEye just published a blog post about this research, which indicates they now believe the likely source of this attack was Korea, not China. The headline to this story has been modified..

Continue reading →


5
Dec 11

Chats With Accused ‘Mega-D’ Botnet Owner?

Recently leaked online chat records may provide the closest look yet at a Russian man awaiting trial in Wisconsin on charges of running a cybercrime machine once responsible for sending between 30 to 40 percent of the world’s junk email.

Oleg Nikolaenko

Oleg Y. Nikolaenko, a 24-year-old who’s been dubbed “The King of Spam,” was arrested by authorities in November 2010 as he visited a car show in Las Vegas. The U.S. Justice Department alleges that Nikolaenko, using the online nickname “Docent” earned hundreds of thousands of dollars using his “Mega-D” botnet, which authorities say infected more than half a million PCs and could send over 10 billion spam messages a day. Nikoalenko has pleaded not guilty to the charges, and is slated to appear in court this week for a status conference (PDF) on his case.

The Justice Department alleges that Nikolaenko spammed on behalf of Lance Atkinson and other members of Affking, an affiliate program that marketed fly-by-night online pharmacies and knockoff designer goods. Atkinson told prosecutors that one of his two largest Russian spamming affiliates used the online moniker Docent. He also said that Docent received payment via an ePassporte account under the name “Genbucks_dcent.” FBI agents later learned that the account was registered in Nikolaenko’s name and address in Russia, and that the email address attached to the account was 4docent@gmail.com.

According to my research, Docent also spammed for other rogue pharmacy programs. In fact, it’s hard to find one that didn’t pay him to send spam. In my Pharma Wars series, I’ve detailed how Russian cybercrime investigators probing the operations of the massive GlavMed/SpamIt rogue pharmacy operation seized thousands of chat logs from one of its principal organizers. The chats were later leaked online and to select journalists. Within those records are hundreds of hours of chats between the owners of the pharmacy program and many of the world’s biggest spammers, including dozens with one of its top earners — Docent.

According to the SpamIt records, Docent earned commissions totaling more than $325,000 promoting SpamIt pharmacy sites through spam between 2007 and 2010. The Docent in the SpamIt database also had his earnings sent to the same ePassporte account identified by the FBI. The Docent in the leaked chats never references himself as Nikolaenko, but in several cases he asks SpamIt coordinators to send documents to him at the 4docent@gmail.com address.

The chats between Docent and Stupin show a young man who is ultra-confident in the value and sheer spam-blasting power of his botnet. Below are the first in a series of conversation snippets between Docent and SpamIt co-administrator Dmitry Stupin. Before each is a brief note providing some context.

In the transcript that follows, Stupin tries to woo Docent to join SpamIt. Docent negotiates a much higher commission rate than is usually given to new spamming partners. The typical rate is 30 percent of each sale, but Docent is a known figure in the spamming underground, and argues that his botnet will bring such massive traffic to the SpamIt pharmacies that he deserves a higher 45 or 50 percent cut of the sales. This conversation was recorded on Feb. 1, 2007.

Stupin:  Hello! You have communicated with ICQ 397061228, I am writing regarding your case, Docent.

Docent: Which case?

Stupin:  Do you want to send spam regarding our partnerka ["partnerka" is Russian slang for a mix of private and semi-public affiliate groups that form to facilitate cybercrime activities].

Docent: Which exactly do you mean? I have not yet communicated with this 397061228.

Stupin: Here is the letter which recently came from  you: “It is usual spam,  GI bases, not opt-in. Big volume of emails. I mail a lot of [competing pharmacy] programs, Bulker, Mailien, SRX. I’m a member of most bulk forums. So if you need references, i can provide them. Usual traffic is 2k+ uniques. Also i need bulk-host.”

Docent: Yes, I got it. It’s just nobody IM’d me.

Stupin: ок) What kind of volumes of spam can you deliver? We are soon deploying our own “partnerka” for spam, we just do not have it right now.

Docent: Volumes are huge, 500 million + / day.

Stupin: Wow! Are you not accidentally on [Spamhaus] ROKSO List ?

Docent: Yes, it’s a list of idiots :), with the exception of a couple of people.

Stupin:  We do contract people for our spam campaigns, but only verified people. We are not publicly opened yet.

Continue reading →


1
Jul 11

Where Have All the Spambots Gone?

First, the good news: The past year has witnessed the decimation of spam volume, the arrests of several key hackers, and the high-profile takedowns of some of the Web’s most notorious botnets. The bad news? The crooks behind these huge crime machines are fighting back — devising new approaches designed to resist even the most energetic takedown efforts.

The volume of junk email flooding inboxes each day is way down from a year ago, as much as a 90 percent decrease according to some estimates. Symantec reports that spam volumes hit their high mark in July 2010, when junk email purveyors were blasting in excess of 225 billion spam messages per day. The company says daily spam volumes now hover between 25 and 50 billion missives daily. Anti-spam experts from Cisco Systems are tracking a similarly precipitous decline, from 300 billion per day in June 2010 to just 40 billion in June 2011.

Spam messages per day, July 2010 - July 2011. Image courtesy Symantec.

There may be many reasons for the drop in junk email volumes, but it would be a mistake to downplay efforts by law enforcement officials and security experts.  In the past year, authorities have taken down some of the biggest botnets and apprehended several top botmasters. Most recently, the FBI worked with dozens of ISPs to kneecap the Coreflood botnet. In April, Microsoft launched an apparently successful sneak attack against Rustock, a botnet once responsible for sending 40 percent of all junk email.

Daily spam volume July 2010 - July 2011. Image courtesy Spamcop.net

In December 2010, the FBI arrested a Russian accused of running the Mega-D botnet. In October 2010, authorities in the Netherlands arrested the alleged creator of the Bredolab botnet and dismantled huge chunks of the botnet. A month earlier, Spamit.com, one of the biggest spammer affiliate programs ever created, was shut down when its creator, Igor Gusev, was named the world’s number one spammer and went into hiding. In August 2010, researchers clobbered the Pushdo botnet, causing spam from that botnet to slow to a trickle.

But botmasters are not idly standing by while their industry is dismantled. Analysts from Kaspersky Lab this week published research on a new version of the TDSS malware (a.k.a. TDL), a sophisticated malicious code family that includes a powerful rootkit component that compromises PCs below the operating system level, making it extremely challenging to detect and remove. The latest version of TDSS — dubbed TDL-4 has already infected 4.5 million PCs; it uses a custom encryption scheme that makes it difficult for security experts to analyze traffic between hijacked PCs and botnet controllers. TDL-4 control networks also send out instructions to infected PCs using a peer-to-peer network that includes multiple failsafe mechanisms.

Continue reading →


3
May 11

Advanced Persistent Tweets: Zero-Day in 140 Characters

The unceasing barrage of targeted email attacks that leverage zero-day software flaws to steal sensitive information from businesses and the U.S. government often are described as being ultra-sophisticated, almost ninja-like in stealth and anonymity. But according to expert analysis of several recent zero-day attacks – including the much publicized break-in at security giant RSA — the Chinese developers of those attack tools left clues aplenty about their identities and locations, with one apparent contender even Tweeting about having newly discovered a vulnerability days in advance of its use in the wild.

Zero-day threats are attacks which exploit security vulnerabilities that a software vendor learns about at the same time as the general public  does;   The vendor has “zero days” to fix the flaw before it gets exploited. RSA and others have labeled recent zero-day attacks as the epitome of the so-called “advanced persistent threat” (APT), a controversial term describing the daily onslaught of digital assaults launched by attackers who are considered highly-skilled, determined and possessed of a long-term perspective on their mission. Because these attacks often result in the theft of sensitive and proprietary information from the government and private industry, the details usually are shrouded in secrecy when law enforcement and national security investigators swoop in.

Open source information available about the tools used in recent attacks labeled APT indicates that some of the actors involved are doing little to cover their tracks: Not only are they potentially identifiable, they don’t seem particularly concerned about suffering any consequences from their actions.

Bragging rights may play a part in the attackers’  lack of duplicity. On Apr. 11, 2011, security experts began publishing information about a new zero-day attack that exploited a previously unknown vulnerability in Adobe‘s Flash Player software, a browser plug-in installed in 96 percent of the world’s Microsoft Windows PCs .  The exploit code was hidden inside a Microsoft Word document titled “Disentangling Industrial Policy and Competition Policy.doc,” and reportedly was emailed to an unknown number of U.S. government employees and contractors.

Four days earlier, on Apr. 7, an individual on Twitter calling himself “Yuange” and adopting the humble motto “No. 1 hacker in China top hacker in the world,” tweeted a small snippet of exploit code, apparently to signal that he had advance knowledge of the attack:

call [0x1111110+0x08].

It wasn’t long before malware researchers were extracting that exact string from the innards of a Flash exploit that was landing in email inboxes around the globe.

Tweeting a key snippet of code hidden in a zero-day exploit in advance of its public release may seem like the hacker equivalent of Babe Ruth pointing to the cheap seats right before nailing a home run. But investigators say the Chinese Internet address used to download the malicious files in the early hours of the April Flash zero-day attacks — 123.123.123.123 — was in some ways bolder than most because that address  would appear highly unusual and memorable to any reasonably vigilant network administrator.

This wasn’t the first time Yuange had bragged about advance knowledge of impending zero-day attacks. On Oct. 27, 2010, he boasted of authoring a zero-day exploit targeting a previously unknown vulnerability in Mozilla’s Firefox Web browser:

Wrote the firefox 0day. You may see “for(inx=0’inx<0x8964;inx++). You should know why 0x8964 here.

That same day, experts discovered that the Web site for the Nobel Peace Prize was serving up malicious software that exploited a new vulnerability in Firefox. An analysis of the attack code published by a member of Mozilla’s security team revealed the exact code snippet Yuange had tweeted.

On February 28, 2011, Yuange taunted on Twitter that new zero-day traps were being set:

ready? new flash 0day is on the way.

On Mar. 14, Adobe acknowledged that a new Flash flaw was being exploited via a booby-trapped Flash component tucked inside of Microsoft Excel files. Three days after that, EMC’s security division RSA dropped a bombshell: Secret files related to its widely used SecurID authentication tokens had been stolen in “an extremely sophisticated cyber attack.” A follow-up blog post from RSA’s Uri River two weeks later stated that the break-in was precipitated by the zero-day Adobe had warned about on Mar. 14, and that the lure used in the attack on RSA was an Excel file named “2011 Recruitment Plan.”

Continue reading →


28
Mar 11

Microsoft Hunting Rustock Controllers

Who controlled the Rustock botnet? The question remains unanswered: Microsoft’s recent takedown of the world’s largest spam engine offered tantalizing new clues to the identity and earnings of the Rustock botmasters. The data shows that Rustock’s curators made millions by pimping rogue Internet pharmacies, but also highlights the challenges that investigators still face in tracking down those responsible for building and profiting from this complex crime machine.

Earlier this month, Microsoft crippled Rustock by convincing a court to let it seize dozens of Rustock control servers that were scattered among several U.S.-based hosting providers. Shortly after that takedown, I began following the money trail to learn who ultimately paid the botnet controllers’ hosts for their services.

According to interviews with investigators involved in the Rustock takedown, approximately one-third of the control servers were rented from U.S. hosting providers by one entity: A small business in Eastern Europe that specializes in reselling hosting services to shadowy individuals who frequent underground hacker forums.

KrebsOnSecurity.com spoke to that reseller. In exchange for the agreement that I not name his operation or his location, he provided payment information about the customer who purchased dozens of servers that were used to manipulate the day-to-day operations of the massive botnet.

The reseller was willing to share information about his client because the customer turned out to be a deadbeat: The customer walked out on two months worth of rent, an outstanding debt of $1,600. The reseller also seemed willing to talk to me because I might be able bend the ear of Spamhaus.org, the anti-spam group that urged ISPs worldwide to block his Internet addresses (several thousand dollars worth of rented servers) shortly after Microsoft announced the Rustock takedown.

I found the reseller advertising his services on a Russian-language forum that caters exclusively to spammers, where he describes the hardware, software and connection speed capabilities of the very servers that he would later rent out to the Rustock botmaster. That solicitation, which was posted on a major spammer forum in January 2010, offered prospective clients flexible terms without setting too many boundaries on what they could do with the servers. A translated version of part of his message:

“I am repeating again that the servers are legitimate, funded by us and belong to our company. To the datacenters, we are responsible to ensure that you are our client, and that you will not break the terms of use. Also, to you we are responsible to make sure that the servers are not going to be closed down because of credit card chargebacks, as it happens with servers funded with stolen credit cards. In conclusion, they do not have an abuse report center, they are suitable for legitimate projects, VPNs and everything else that does not lead to problems and complaints to the data center from active Internet users. Please, take it in consideration, so that nobody is pissed off and there is no bad impression from our partnership.”

The reseller said he had no idea that his customer was using the servers to control the Rustock botnet, but he hastened to add that this particular client didn’t attract too much attention to himself. According to the reseller, the servers he resold to the Rustock botmaster generated just two abuse complaints from the Internet service providers (ISPs) that hosted those servers. Experts say this makes sense because botnet control servers typically generate few abuse complaints, because they are almost never used for the sort of activity that usually prompts abuse reports, such as sending spam or attacking others online. Instead, the servers only were used to coordinate the activities of hundreds of thousands of PCs infected with Rustock, periodically sending them program updates and new spamming instructions.

The reseller was paid for the servers from an account at WebMoney, a virtual currency similar to PayPal but more popular among Russian and Eastern European consumers. The reseller shared the unique numeric ID attached to that WebMoney account — WebMoney purse “Z166284889296.” That purse belonged to an “attested” WebMoney account, meaning that the account holder at some point had to verify his identity by presenting an official Russian passport at a WebMoney office. A former law enforcement officer involved in the Rustock investigation said the name attached to that attested account was “Vladimir Shergin.” According to the reseller, the client stated in an online chat that he was from Saint Petersburg, Russia.

Continue reading →


21
Mar 11

Homegrown: Rustock Botnet Fed by U.S. Firms

Aaron Wendel opened the doors of his business to some unexpected visitors on the morning of Mar. 16, 2011. The chief technology officer of Kansas City based hosting provider Wholesale Internet found that two U.S. marshals, a pair of computer forensics experts and a Microsoft lawyer had come calling, armed with papers allowing them to enter the facility and to commandeer computer hard drives and portions of the hosting firm’s network. Anyone attempting to interfere would be subject to arrest and prosecution.

Weeks earlier, Microsoft had convinced a federal judge (PDF)  to let the software giant seize control of server hard drives and reroute Internet addresses as part of a carefully timed takedown of the Rustock botnet, which had long reigned as the world’s most active spam-spewing crime machine.

In tandem with the visit to Wholesale Internet, Microsoft employees and U.S. marshals were serving similar orders at several other hosting providers at locations around country.  Microsoft’s plan of attack — which it spent about six months hatching with the help of a tightly knit group of industry and academic partners — was to stun the Rustock botnet, by disconnecting more than 100 control servers that the botnet was using to communicate with hundreds of thousands of infected Windows PCs.

Only two of the control servers were located outside the United States; the rest operated from hosting providers here in the US, many at relatively small ISPs in Middle America.

Concentrations of Rustock control networks.

Microsoft was careful not to make any accusations that hosting providers were complicit in helping the Rustock botmasters; however, some of these control servers existed for more than a year, and most likely would have continued to operate undisturbed had Microsoft and others not intervened. Using data gathered by Milpitas, Calif. based security firm FireEye, which assisted Microsoft in the takedown, I was able to plot the location and lifetime of each control server (the map above is clickable and should let you drill down to the details of each control server; the raw data is here). The average life of each controller was 251 days — a little over eight months.

Wholesale Internet’s Wendel said his organization takes action against any customers that appear to be violating the company’s terms of use or its policies. But he insisted that the visit by Microsoft and the marshals was the first time he’d heard that any of the 16 Rustock command and control servers were located on his network.

“To be perfectly honest with you, we never heard of Rustock until Wednesday,” Wendel said in a phone interview last Friday. Wendel also said he  hadn’t heard anything about the problematic servers from either Spamhaus or Shadowserver, which allow ISPs and hosting providers to receive reports about apparent botnet control servers and bot infections on their networks. Both Shadowserver and Spamhaus dispute this claim, saying that while they certainly did not alert Wholesale to all of the problem Internet addresses that it may have had on its network, they filed several reports with the company over the past six months that should have given the company cause to take a closer look at its customers and systems.

Continue reading →