Posts Tagged: DNS


4
Feb 19

Crooks Continue to Exploit GoDaddy Hole

Godaddy.com, the world’s largest domain name registrar, recently addressed an authentication weakness that cybercriminals were using to blast out spam through legitimate, dormant domains. But several more recent malware spam campaigns suggest GoDaddy’s fix hasn’t gone far enough, and that scammers likely still have a sizable arsenal of hijacked GoDaddy domains at their disposal.

On January 22, KrebsOnSecurity published research showing that crooks behind a series of massive sextortion and bomb threat spam campaigns throughout 2018 — an adversary that’s been dubbed “Spammy Bear” —  achieved an unusual amount of inbox delivery by exploiting a weakness at GoDaddy which allowed anyone to add a domain to their GoDaddy account without validating that they actually owned the domain.

Spammy Bear targeted dormant but otherwise legitimate domains that had one thing in common: They all at one time used GoDaddy’s hosted Domain Name System (DNS) service. Researcher Ron Guilmette discovered that Spammy Bear was able to hijack thousands of these dormant domains for spam simply by registering free accounts at GoDaddy and telling the company’s automated DNS service to allow the sending of email with those domains from an Internet address controlled by the spammers.

Very soon after that story ran, GoDaddy said it had put in place a fix for the problem, and had scrubbed more than 4,000 domain names used in the spam campaigns that were identified in my Jan. 22 story. But on or around February 1, a new spam campaign that leveraged similarly hijacked domains at GoDaddy began distributing Gand Crab, a potent strain of ransomware.

As noted in a post last week at the blog MyOnlineSecurity, the Gand Crab campaign used a variety of lures, including fake DHL shipping notices and phony AT&T e-fax alerts. The domains documented by MyOnlineSecurity all had their DNS records altered between Jan. 31 and Feb. 1 to allow the sending of email from Internet addresses tied to two ISPs identified in my original Jan. 22 report on the GoDaddy weakness.

“What makes these malware laden emails much more likely to be delivered is the fact that the sending domains all have a good reputation,” MyOnlineSecurity observed. “There are dozens, if not hundreds of domains involved in this particular campaign. Almost all the domains have been registered for many years, some for more than 10 years.”

A “passive DNS” lookup shows the DNS changes made by the spammers on Jan. 31 for one of the domains used in the Gand Crab spam campaign documented by MyOnlineSecurity. Image: Farsight Security.

In a statement provided to KrebsOnSecurity, GoDaddy said the company was confident the steps it took to address the problem were working as intended, and that GoDaddy had simply overlooked the domains abused in the recent GandCrab spam campaign.

“The domains used in the Gand Crab campaign were modified before then, but we missed them in our initial sweep,” GoDaddy spokesperson Dan Race said. “While we are otherwise confident of the mitigation steps we took to prevent the dangling DNS issue, we are working to identify any other domains that need to be fixed.”

“We do not believe it is possible for a person to hijack the DNS of one or more domains using the same tactics as used in the Spammy Bear and Gand Crab campaigns,” Race continued. “However, we are assessing if there are other methods that may be used to achieve the same results, and we continue our normal monitoring for account takeover. We have also set up a reporting alias at dns-spam-concerns@godaddy.com to make it easier to report any suspicious activity or any details that might help our efforts to stop this kind of abuse.”

That email address is likely to receive quite a few tips in the short run. Virus Bulletin editor Martijn Grooten this week published his analysis on a January 29 malware email campaign that came disguised as a shipping notice from UPS. Grooten said the spam intercepted from that campaign included links to an Internet address that was previously used to distribute GandCrab, and that virtually all of the domains seen sending the fake UPS notices used one of two pairs of DNS servers managed by GoDaddy.

“The majority of domains, which we think had probably had their DNS compromised, still point to the same IP address though,” Grooten wrote. That IP address is currently home to a Web site that sells stolen credit card data.

The fake UPS message used in a Jan. 29 Gand Crab malware spam campaign. Source: Virus Bulletin.

Grooten told KrebsOnSecurity he suspects criminals may have succeeded at actually compromising several of GoDaddy’s hosted DNS servers. For one thing, he said, the same pair (sometimes two pairs) of name servers keep appearing in the same campaign.

“In quite a few campaigns we saw domains used that were alphabetically close, [and] there are other domains used that had moved away from GoDaddy before these campaigns, yet were still used,” Grooten said. “It’s also interesting to note that hundreds — and perhaps thousands — of domains had their DNS changed within a short period of time. Such a thing is hard to do if you have to log into individual accounts.”

GoDaddy said there has been no such breach.

“Our DNS servers have not been compromised,” Race said. “The examples provided were dangled domains that had zone files created by the threat actor prior to when we implemented our mitigation on January 23. These domain names were parked until the threat actors activated them. They had the ability to do that because they owned the zone files already. We’re continuing to review customer accounts for other potential zone entries.”
Continue reading →


22
Jan 19

Bomb Threat, Sextortion Spammers Abused Weakness at GoDaddy.com

Two of the most disruptive and widely-received spam email campaigns over the past few months — including an ongoing sextortion email scam and a bomb threat hoax that shut down dozens of schools, businesses and government buildings late last year — were made possible thanks to an authentication weakness at GoDaddy.com, the world’s largest domain name registrar, KrebsOnSecurity has learned.

Perhaps more worryingly, experts warn this same weakness that let spammers hijack domains tied to GoDaddy also affects a great many other major Internet service providers, and is actively being abused to launch phishing and malware attacks which leverage dormant Web site names currently owned and controlled by some of the world’s most trusted corporate names and brands.

In July 2018, email users around the world began complaining of receiving spam which began with a password the recipient used at some point in the past and threatened to release embarrassing videos of the recipient unless a bitcoin ransom was paid. On December 13, 2018, a similarly large spam campaign was blasted out, threatening that someone had planted bombs within the recipient’s building that would be detonated unless a hefty bitcoin ransom was paid by the end of the business day.

Experts at Cisco Talos and other security firms quickly drew parallels between the two mass spam campaigns, pointing to a significant overlap in Russia-based Internet addresses used to send the junk emails. Yet one aspect of these seemingly related campaigns that has been largely overlooked is the degree to which each achieved an unusually high rate of delivery to recipients.

Large-scale spam campaigns often are conducted using newly-registered or hacked email addresses, and/or throwaway domains. The trouble is, spam sent from these assets is trivial to block because anti-spam and security systems tend to discard or mark as spam any messages that appear to come from addresses which have no known history or reputation attached to them.

However, in both the sextortion and bomb threat spam campaigns, the vast majority of the email was being sent through Web site names that had already existed for some time, and indeed even had a trusted reputation. Not only that, new research shows many of these domains were registered long ago and are still owned by dozens of Fortune 500 and Fortune 1000 companies. 

That’s according to Ron Guilmette, a dogged anti-spam researcher. Researching the history and reputation of thousands of Web site names used in each of the extortionist spam campaigns, Guilmette made a startling discovery: Virtually all of them had at one time received service from GoDaddy.com, a Scottsdale, Ariz. based domain name registrar and hosting provider.

Guilmette told KrebsOnSecurity he initially considered the possibility that GoDaddy had been hacked, or that thousands of the registrar’s customers perhaps had their GoDaddy usernames and passwords stolen.

But as he began digging deeper, Guilmette came to the conclusion that the spammers were exploiting an obscure — albeit widespread — weakness among hosting companies, cloud providers and domain registrars that was first publicly detailed in 2016.

EARLY WARNING SIGNS

In August 2016, security researcher Matthew Bryant wrote about a weakness that could be used to hijack email service for 20,000 established domain names at a U.S. based hosting provider. A few months later, Bryant warned that the same technique could be leveraged to send spam from more than 120,000 trusted domains across multiple providers. And Guilmette says he now believes the attack method detailed by Bryant also explains what’s going on in the more recent sextortion and bomb threat spams.

Grasping the true breadth of Bryant’s prescient discovery requires a brief and simplified primer on how Web sites work. Your Web browser knows how to find a Web site name like example.com thanks to the global Domain Name System (DNS), which serves as a kind of phone book for the Internet by translating human-friendly Web site names (example.com) into numeric Internet address that are easier for computers to manage.

When someone wants to register a domain at a registrar like GoDaddy, the registrar will typically provide two sets of DNS records that the customer then needs to assign to his domain. Those records are crucial because they allow Web browsers to figure out the Internet address of the hosting provider that’s serving that Web site domain. Like many other registrars, GoDaddy lets new customers use their managed DNS services for free for a period of time (in GoDaddy’s case it’s 30 days), after which time customers must pay for the service.

The crux of Bryant’s discovery was that the spammers in those 2016 campaigns learned that countless hosting firms and registrars would allow anyone to add a domain to their account without ever validating that the person requesting the change actually owned the domain. Here’s what Bryant wrote about the threat back in 2016:

“In addition to the hijacked domains often having past history and a long age, they also have WHOIS information which points to real people unrelated to the person carrying out the attack. Now if an attacker launches a malware campaign using these domains, it will be harder to pinpoint who/what is carrying out the attack since the domains would all appear to be just regular domains with no observable pattern other than the fact that they all use cloud DNS. It’s an attacker’s dream, troublesome attribution and an endless number of names to use for malicious campaigns.”

SAY WHAT?

For a more concrete example of what’s going on here, we’ll look at just one of the 4,000+ domains that Guilmette found were used in the Dec. 13, 2018 bomb threat hoax. Virtualfirefox.com is a domain registered via GoDaddy in 2013 and currently owned by The Mozilla Corporation, a wholly owned subsidiary of the Mozilla Foundation — the makers of the popular Firefox Web browser.

The domain’s registration has been renewed each year since its inception, but the domain itself has sat dormant for some time. When it was initially set up, it took advantage of two managed DNS servers assigned to it by GoDaddy — ns17.domaincontrol.com, and ns18.domaincontrol.com.

GoDaddy is a massive hosting provider, and it has more than 100 such DNS servers to serve the needs of its clients. To hijack this domain, the attackers in the December 2018 spam campaign needed only to have created a free account at GoDaddy that was assigned the exact same DNS servers handed out to Virtualfirefox.com (ns17.domaincontrol.com and ns18.domaincontrol.com). After that, the attackers simply claim ownership over the domain, and tell GoDaddy to allow the sending of email with that domain from an Internet address they control.

Mozilla spokesperson Ellen Canale said Mozilla took ownership of virtualfirefox.com in September 2017 after a trademark dispute, but that the DNS nameserver for the record was not reset until January of 2019.

“This oversight created a state where the DNS pointed to a server controlled by a third party, leaving it vulnerable to misuse,” Canale said. “We’ve reviewed the configuration of both our registrar and nameservers and have found no indication of misuse. In addition to addressing the immediate problem, we have reviewed the entire catalog of properties we own to ensure they are properly configured.”

According to both Guilmette and Bryant, this type of hijack is possible because GoDaddy — like many other managed DNS providers — does little to check whether someone with an existing account (free or otherwise) who is claiming ownership over a given domain actually controls that domain name.

Contacted by KrebsOnSecurity, GoDaddy acknowledged the authentication weakness documented by Guilmette.

“After investigating the matter, our team confirmed that a threat actor(s) abused our DNS setup process,” the company said in an emailed statement.

“We’ve identified a fix and are taking corrective action immediately,” the statement continued. “While those responsible were able to create DNS entries on dormant domains, at no time did account ownership change nor was customer information exposed.” Continue reading →


27
Oct 16

Are the Days of “Booter” Services Numbered?

It may soon become easier for Internet service providers to anticipate and block certain types of online assaults launched by Web-based attack-for-hire services known as “booter” or “stresser” services, new research released today suggests.

The findings come from researchers in Germany who’ve been studying patterns that emerge when miscreants attempt to mass-scan the entire Internet looking for systems useful for launching these digital sieges — known as “distributed denial-of-service” or DDoS attacks.

ddosbomb

To understand the significance of their research, it may help to briefly examine how DDoS attacks have evolved. Not long ago, if one wanted to take down large Web site, one had to build and maintain a large robot network, or “botnet,” of hacked computers — which is a fairly time intensive, risky and technical endeavor.

These days, however, even the least sophisticated Internet user can launch relatively large DDoS attacks just by paying a few bucks for a subscription to one of dozens of booter or stresser services, some of which even accept credit cards and PayPal payments.

These Web-based DDoS-for-hire services don’t run on botnets: They generally employ a handful of powerful servers that are rented from some dodgy “bulletproof” hosting provider. The booter service accepts payment and attack instructions via a front end Web site that is hidden behind Cloudflare (a free DDoS protection service).

But the back end of the booter service is where the really interesting stuff happens. Virtually all of the most powerful and effective attack types used by booter services rely on a technique called traffic amplification and reflection, in which the attacker can reflect or “spoof” his traffic from one or more third-party machines toward the intended target.

In this type of assault, the attacker sends a message to a third party, while spoofing the Internet address of the victim. When the third party replies to the message, the reply is sent to the victim — and the reply is much larger than the original message, thereby amplifying the size of the attack.

To find vulnerable systems that can be leveraged this way, booters employ large-scale Internet scanning services that constantly seek to refresh the list of systems that can be used for amplification and reflection attacks. They do this because, as research has shown (PDF), anywhere from 40-50 percent of the amplifiers vanish or are reassigned new Internet addresses after one week.

Enter researchers from Saarland University in Germany, as well as the Yokohama National University and National Institute of Information and Communications Technology — both in Japan. In a years-long project first detailed in 2015, the researchers looked for scanning that appeared to be kicked off by ne’er-do-wells running booter services.

To accomplish this, the research team built a kind of distributed “honeypot” system — which they dubbed “AmpPot” — designed to mimic services known to be vulnerable to amplification attacks, such as DNS and NTP floods.

“To make them attractive to attackers, our honeypots send back legitimate responses,” the researchers wrote in a 2015 paper (PDF). “Attackers, in turn, will abuse these honeypots as amplifiers, which allows us to observe ongoing attacks, their victims, and the DDoS techniques. To prevent damage caused by our honeypots, we limit the response rate. This way, while attackers can still find these ratelimited honeypots, the honeypots stop replying in the face of attacks.”

In that 2015 paper, the researchers said they deployed 21 globally-distributed AmpPot instances, which observed more than 1.5 million attacks between February and May 2015. Analyzing the attacks more closely, they found that more than 96% of the attacks stem from single sources, such as booter services.

“When focusing on amplification DDoS attacks, we find that almost all of them (>96%) are caused by single sources (e.g. booters), and not botnets,” the team concluded. “However, we sadly do not have the numbers to compare this [to] DoS attacks in general.”

Many large-scale Internet scans like the ones the researchers sought to measure are launched by security firms and other researchers, so the team needed a way to differentiate between scans launched by booter services and those conducted for research or other benign purposes.

“To distinguish between scans performed by researchers and scans performed with malicious intent we relied on a simple assumption: That no attack would be based on the results of a scan performed by (ethical) researchers,” said Johannes Krupp, one of the main authors of the report. “In fact, thanks to our methodology, we do not have to make this distinction upfront, but we can rather look at the results and say: ‘We found attacks linked to this scanner, therefore this scanner must have been malicious.’ If a scan was truly performed by benign parties, we will not find attacks linked to it.”

SECRET IDENTIFIERS

What’s new in the paper being released today by students at Saarland University’s Center for IT-Security, Privacy and Accountability (CISPA) is the method by which the researchers were able to link these mass-scans to the very amplification attacks that follow soon after.

The researchers worked out a way to encode a secret identifier into the set of AmpPot honeypots that any subsequent attack will use, which varies per scan source. They then tested to see if the scan infrastructure was also used to actually launch (and not just to prepare) the attacks. Continue reading →


21
Oct 16

DDoS on Dyn Impacts Twitter, Spotify, Reddit

Criminals this morning massively attacked Dyn, a company that provides core Internet services for Twitter, SoundCloud, Spotify, Reddit and a host of other sites, causing outages and slowness for many of Dyn’s customers.

Twitter is experiencing problems, as seen through the social media platform Hootsuite.

Twitter is experiencing problems, as seen through the social media platform Hootsuite.

In a statement, Dyn said that this morning, October 21, Dyn received a global distributed denial of service (DDoS) attack on its DNS infrastructure on the east coast starting at around 7:10 a.m. ET (11:10 UTC).

“DNS traffic resolved from east coast name server locations are experiencing a service interruption during this time. Updates will be posted as information becomes available,” the company wrote.

DYN encouraged customers with concerns to check the company’s status page for updates and to reach out to its technical support team.

A DDoS is when crooks use a large number of hacked or ill-configured systems to flood a target site with so much junk traffic that it can no longer serve legitimate visitors.

DNS refers to Domain Name System services. DNS is an essential component of all Web sites, responsible for translating human-friendly Web site names like “example.com” into numeric, machine-readable Internet addresses. Anytime you send an e-mail or browse a Web site, your machine is sending a DNS look-up request to your Internet service provider to help route the traffic.

ANALYSIS

The attack on DYN comes just hours after DYN researcher Doug Madory presented a talk on DDoS attacks in Dallas, Texas at a meeting of the North American Network Operators Group (NANOG). Madory’s talk — available here on Youtube.com — delved deeper into research that he and I teamed up on to produce the data behind the story DDoS Mitigation Firm Has History of Hijacks. Continue reading →


25
Sep 16

The Democratization of Censorship

John Gilmore, an American entrepreneur and civil libertarian, once famously quipped that “the Internet interprets censorship as damage and routes around it.” This notion undoubtedly rings true for those who see national governments as the principal threats to free speech.

However, events of the past week have convinced me that one of the fastest-growing censorship threats on the Internet today comes not from nation-states, but from super-empowered individuals who have been quietly building extremely potent cyber weapons with transnational reach.

underwater

More than 20 years after Gilmore first coined that turn of phrase, his most notable quotable has effectively been inverted — “Censorship can in fact route around the Internet.” The Internet can’t route around censorship when the censorship is all-pervasive and armed with, for all practical purposes, near-infinite reach and capacity. I call this rather unwelcome and hostile development the “The Democratization of Censorship.”

Allow me to explain how I arrived at this unsettling conclusion. As many of you know, my site was taken offline for the better part of this week. The outage came in the wake of a historically large distributed denial-of-service (DDoS) attack which hurled so much junk traffic at Krebsonsecurity.com that my DDoS protection provider Akamai chose to unmoor my site from its protective harbor.

Let me be clear: I do not fault Akamai for their decision. I was a pro bono customer from the start, and Akamai and its sister company Prolexic have stood by me through countless attacks over the past four years. It just so happened that this last siege was nearly twice the size of the next-largest attack they had ever seen before. Once it became evident that the assault was beginning to cause problems for the company’s paying customers, they explained that the choice to let my site go was a business decision, pure and simple.

Nevertheless, Akamai rather abruptly informed me I had until 6 p.m. that very same day — roughly two hours later — to make arrangements for migrating off their network. My main concern at the time was making sure my hosting provider wasn’t going to bear the brunt of the attack when the shields fell. To ensure that absolutely would not happen, I asked Akamai to redirect my site to 127.0.0.1 — effectively relegating all traffic destined for KrebsOnSecurity.com into a giant black hole.

Today, I am happy to report that the site is back up — this time under Project Shield, a free program run by Google to help protect journalists from online censorship. And make no mistake, DDoS attacks — particularly those the size of the assault that hit my site this week — are uniquely effective weapons for stomping on free speech, for reasons I’ll explore in this post.

Google's Project Shield is now protecting KrebsOnSecurity.com

Google’s Project Shield is now protecting KrebsOnSecurity.com

Why do I speak of DDoS attacks as a form of censorship? Quite simply because the economics of mitigating large-scale DDoS attacks do not bode well for protecting the individual user, to say nothing of independent journalists.

In an interview with The Boston Globe, Akamai executives said the attack — if sustained — likely would have cost the company millions of dollars. In the hours and days following my site going offline, I spoke with multiple DDoS mitigation firms. One offered to host KrebsOnSecurity for two weeks at no charge, but after that they said the same kind of protection I had under Akamai would cost between $150,000 and $200,000 per year.

Ask yourself how many independent journalists could possibly afford that kind of protection money? A number of other providers offered to help, but it was clear that they did not have the muscle to be able to withstand such massive attacks.

I’ve been toying with the idea of forming a 501(c)3 non-profit organization — ‘The Center for the Defense of Internet Journalism’, if you will — to assist Internet journalists with obtaining the kind of protection they may need when they become the targets of attacks like the one that hit my site.  Maybe a Kickstarter campaign, along with donations from well-known charitable organizations, could get the ball rolling.  It’s food for thought. Continue reading →


21
Sep 16

KrebsOnSecurity Hit With Record DDoS

On Tuesday evening, KrebsOnSecurity.com was the target of an extremely large and unusual distributed denial-of-service (DDoS) attack designed to knock the site offline. The attack did not succeed thanks to the hard work of the engineers at Akamai, the company that protects my site from such digital sieges. But according to Akamai, it was nearly double the size of the largest attack they’d seen previously, and was among the biggest assaults the Internet has ever witnessed.
iotstuf

The attack began around 8 p.m. ET on Sept. 20, and initial reports put it at approximately 665 Gigabits of traffic per second. Additional analysis on the attack traffic suggests the assault was closer to 620 Gbps in size, but in any case this is many orders of magnitude more traffic than is typically needed to knock most sites offline.

Martin McKeay, Akamai’s senior security advocate, said the largest attack the company had seen previously clocked in earlier this year at 363 Gbps. But he said there was a major difference between last night’s DDoS and the previous record holder: The 363 Gpbs attack is thought to have been generated by a botnet of compromised systems using well-known techniques allowing them to “amplify” a relatively small attack into a much larger one.

In contrast, the huge assault this week on my site appears to have been launched almost exclusively by a very large botnet of hacked devices.

The largest DDoS attacks on record tend to be the result of a tried-and-true method known as a DNS reflection attack. In such assaults, the perpetrators are able to leverage unmanaged DNS servers on the Web to create huge traffic floods.

Ideally, DNS servers only provide services to machines within a trusted domain. But DNS reflection attacks rely on consumer and business routers and other devices equipped with DNS servers that are (mis)configured to accept queries from anywhere on the Web. Attackers can send spoofed DNS queries to these so-called “open recursive” DNS servers, forging the request so that it appears to come from the target’s network. That way, when the DNS servers respond, they reply to the spoofed (target) address.

The bad guys also can amplify a reflective attack by crafting DNS queries so that the responses are much bigger than the requests. They do this by taking advantage of an extension to the DNS protocol that enables large DNS messages. For example, an attacker could compose a DNS request of less than 100 bytes, prompting a response that is 60-70 times as large. This “amplification” effect is especially pronounced if the perpetrators query dozens of DNS servers with these spoofed requests simultaneously.

But according to Akamai, none of the attack methods employed in Tuesday night’s assault on KrebsOnSecurity relied on amplification or reflection. Rather, many were garbage Web attack methods that require a legitimate connection between the attacking host and the target, including SYN, GET and POST floods.

That is, with the exception of one attack method: Preliminary analysis of the attack traffic suggests that perhaps the biggest chunk of the attack came in the form of traffic designed to look like it was generic routing encapsulation (GRE) data packets, a communication protocol used to establish a direct, point-to-point connection between network nodes. GRE lets two peers share data they wouldn’t be able to share over the public network itself.

“Seeing that much attack coming from GRE is really unusual,” Akamai’s McKeay said. “We’ve only started seeing that recently, but seeing it at this volume is very new.” Continue reading →


8
Aug 12

Triple DDoS vs. KrebsOnSecurity

“When nobody hates you, nobody knows you’re alive.” – Diplomacy, by Chris Smither

During the last week of July, a series of steadily escalating cyber attacks directed at my Web site and hosting provider prevented many readers from being able to reach the site or read the content via RSS. Sorry about that. What follows is a post-mortem on those digital sieges, which featured a mix of new and old-but-effective attack methods.

Junk traffic sent by a DNS amplification attack.

I still don’t know who was attacking my site or why. It’s not as if the perpetrator(s) sent a love letter along with the traffic flood. There was one indication that a story I published just hours before the attacks began — about a service for mass-registering domain names used for malware, spam and other dodgy business — may have struck a nerve: In one of the attacks, all of the assailing systems were instructed to load that particular story many times per second.

Oddly enough, the activity began just one day after I’d signed up with Prolexic. The Hollywood, Fla. based company helps businesses fend off distributed denial of service (DDoS) attacks, assaults in which miscreants knock targeted sites offline by flooding them with garbage traffic. Prolexic was among several anti-DDoS companies that offered to help earlier this year, when KrebsOnSecurity.com came under a separate spate of debilitating attacks.

The first DDoS campaigns consisted of several hundred systems repeatedly requesting image-heavy pages on my site. Prolexic’s analysts say the traffic signatures of these attacks matched that of a family of kits sold in the underground that allow anyone to quickly create their own botnet specifically for launching DDoS attacks. Both are believed to have been created by the same individual(s) behind the Dirt Jumper DDoS toolkit. The traffic signatures from the attack strongly suggest the involvement of two Dirt Jumper progeny: Di-BoTNet and Pandora.

Image courtesy Prolexic

Pandora is the latest in the Dirt Jumper family, and features four different attack methods. According to Prolexic, the one used against KrebsOnSecurity.com was Attack Type 4, a.k.a “Max Flood”; this method carries a fairly unique signature of issuing POST requests against a server that are over a million bytes in length.

Pandora’s creators boast that it only takes 10 PCs infected with the DDoS bot to bring down small sites, and about 30 bots to put down a mid-sized site that lacks protection against DDoS attacks. They claim 1,000 Pandora bots are enough to bring Russian search engine giant yandex.ru to a crawl, but that strikes me as a bit of salesmanship and exaggeration. Prolexic said more than 1,500 Pandora-infected bots were used in the assault on my site.

Continue reading →


4
May 11

RSA Among Dozens of Firms Breached by Zero-Day Attacks

This is the second installment of a multi-part series examining the tools and tactics used by attackers in the RSA breach and other recent network intrusions characterized as “ultra-sophisticated” and “advanced persistent threats.”  If you missed the first piece, please check out Advanced Persistent Tweets: Zero-Day in 140 Characters.

The recent data breach at security industry giant RSA was disconcerting news to the security community: RSA claims to be “the premier provider of security, risk, and compliance solutions for business acceleration” and the “chosen security partner of more than 90 percent of the Fortune 500.”

The hackers who broke into RSA appear to have leveraged some of the very same Web sites, tools and services used in that attack to infiltrate dozens of other companies during the past year, including some of the Fortune 500 companies protected by RSA, new information suggests. What’s more, the assailants moved their operations from those sites very recently, after their locations were revealed in a report published online by the U.S. Computer Emergency Readiness Team (US-CERT), a division of the U.S. Department of Homeland Security.

In RSA’s explanation of the attack, it pointed to three domains that it claimed were used to download malicious software and to siphon sensitive data taken from its internal networks: Good[DOT]mincesur[DOT]com, up82673[DOT]hopto[DOT]org and www[DOT]cz88[DOT]net. But according to interviews with several security experts who keep a close eye on these domains, the Web sites in question weren’t merely one-time attack staging grounds: They had earned a reputation as launch pads for the same kind of attacks over at least a 12 month period prior to the RSA breach disclosure.

What’s more, the same domains were sending and receiving Internet connections from dozens of Fortune 500 companies during that time, according to Atlanta-based Damballa, a company that mines data about malware attacks using a network of sensors deployed at Internet service providers and large enterprises around the world. Damballa monitors the domain name system (DNS) servers at those networks, looking for traffic between known good hosts and known or suspected hostile locations.

Gunter Ollmann, Damballa’s vice president of research, said that for more than a year his company has been monitoring the three malicious sites that RSA said were involved in the theft of its intellectual property, and that many other major companies have had extensive communications with those hostile domains during that time. He added that his company is not in a position to name the other companies impacted by the breach, and that Damballa is helping federal authorities with ongoing investigations.

“There is lots of malware that have relied on those domains for command and control,” Ollmann said. “We know who the victims are, roughly how many devices within those victim organizations were compromised, and are still compromised.  RSA was not the only victim of these attacks.”

Continue reading →