Posts Tagged: Digital Ocean


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 →


8
Sep 16

Israeli Online Attack Service ‘vDOS’ Earned $600,000 in Two Years

vDOS  a “booter” service that has earned in excess of $600,000 over the past two years helping customers coordinate more than 150,000 so-called distributed denial-of-service (DDoS) attacks designed to knock Web sites offline — has been massively hacked, spilling secrets about tens of thousands of paying customers and their targets.

The vDOS database, obtained by KrebsOnSecurity.com at the end of July 2016, points to two young men in Israel as the principal owners and masterminds of the attack service, with support services coming from several young hackers in the United States.

The vDos home page.

The vDos home page.

To say that vDOS has been responsible for a majority of the DDoS attacks clogging up the Internet over the past few years would be an understatement. The various subscription packages to the service are sold based in part on how many seconds the denial-of-service attack will last. And in just four months between April and July 2016, vDOS was responsible for launching more than 277 million seconds of attack time, or approximately 8.81 years worth of attack traffic.

Let the enormity of that number sink in for a moment: That’s nearly nine of what I call “DDoS years” crammed into just four months. That kind of time compression is possible because vDOS handles hundreds — if not thousands — of concurrent attacks on any given day.

Although I can’t prove it yet, it seems likely that vDOS is responsible for several decades worth of DDoS years. That’s because the data leaked in the hack of vDOS suggest that the proprietors erased all digital records of attacks that customers launched between Sept. 2012 (when the service first came online) and the end of March 2016.

HOW vDOS GOT HACKED

The hack of vDOS came about after a source was investigating a vulnerability he discovered on a similar attack-for-hire service called PoodleStresser. The vulnerability allowed my source to download the configuration data for PoodleStresser’s attack servers, which pointed back to api.vdos-s[dot]com. PoodleStresser, as well as a large number of other booter services, appears to rely exclusively on firepower generated by vDOS.

From there, the source was able to exploit a more serious security hole in vDOS that allowed him to dump all of the service’s databases and configuration files, and to discover the true Internet address of four rented servers in Bulgaria (at Verdina.net) that are apparently being used to launch the attacks sold by vDOS. The DDoS-for-hire service is hidden behind DDoS protection firm Cloudflare, but its actual Internet address is 82.118.233.144.

vDOS had a reputation on cybercrime forums for prompt and helpful customer service, and the leaked vDOS databases offer a fascinating glimpse into the logistical challenges associated with running a criminal attack service online that supports tens of thousands of paying customers — a significant portion of whom are all trying to use the service simultaneously.

Multiple vDOS tech support tickets were filed by customers who complained that they were unable to order attacks on Web sites in Israel. Responses from the tech support staff show that the proprietors of vDOS are indeed living in Israel and in fact set the service up so that it was unable to attack any Web sites in that country — presumably so as to not attract unwanted attention to their service from Israeli authorities. Here are a few of those responses:

(‘4130′,’Hello `d0rk`,\r\nAll Israeli IP ranges have been blacklisted due to security reasons.\r\n\r\nBest regards,\r\nP1st.’,’03-01-2015 08:39),

(‘15462′,’Hello `g4ng`,\r\nMh, neither. I\’m actually from Israel, and decided to blacklist all of them. It\’s my home country, and don\’t want something to happen to them :)\r\n\r\nBest regards,\r\nDrop.’,’11-03-2015 15:35),

(‘15462′,’Hello `roibm123`,\r\nBecause I have an Israeli IP that is dynamic.. can\’t risk getting hit/updating the blacklist 24/7.\r\n\r\nBest regards,\r\nLandon.’,’06-04-2015 23:04),

(‘4202′,’Hello `zavi156`,\r\nThose IPs are in israel, and we have all of Israel on our blacklist. Sorry for any inconvinience.\r\n\r\nBest regards,\r\nJeremy.’,’20-05-2015 10:14),

(‘4202′,’Hello `zavi156`,\r\nBecause the owner is in Israel, and he doesn\’t want his entire region being hit offline.\r\n\r\nBest regards,\r\nJeremy.’,’20-05-2015 11:12),

(‘9057′,’There is a option to buy with Paypal? I will pay more than $2.5 worth.\r\nThis is not the first time I am buying booter from you.\r\nIf no, Could you please ask AplleJack? I know him from Israel.\r\nThanks.’,’21-05-2015 12:51),

(‘4120′,’Hello `takedown`,\r\nEvery single IP that\’s hosted in israel is blacklisted for safety reason. \r\n\r\nBest regards,\r\nAppleJ4ck.’,’02-09-2015 08:57),

WHO RUNS vDOS?

As we can see from the above responses from vDOS’s tech support, the owners and operators of vDOS are young Israeli hackers who go by the names P1st a.k.a. P1st0, and AppleJ4ck. The two men market their service mainly on the site hackforums[dot]net, selling monthly subscriptions using multiple pricing tiers ranging from $20 to $200 per month. AppleJ4ck hides behind the same nickname on Hackforums, while P1st goes by the alias “M30w” on the forum.

Some of P1st/M30W's posts on Hackforums regarding his service vDOS.

Some of P1st/M30W’s posts on Hackforums regarding his service vDOS.

vDOS appears to be the longest-running booter service advertised on Hackforums, and it is by far and away the most profitable such business. Records leaked from vDOS indicate that since July 2014, tens of thousands of paying customers spent a total of more than $618,000 at the service using Bitcoin and PayPal.

Incredibly, for brief periods the site even accepted credit cards in exchange for online attacks, although it’s unclear how much the site might have made in credit card payments because the information is not in the leaked databases.

The Web server hosting vDOS also houses several other sites, including huri[dot]biz, ustress[dot]io, and vstress[dot]net. Virtually all of the administrators at vDOS have an email account that ends in v-email[dot]org, a domain that also is registered to an Itay Huri with a phone number that traces back to Israel.

The proprietors of vDOS set their service up so that anytime a customer asked for technical assistance the site would blast a text message to six different mobile numbers tied to administrators of the service, using an SMS service called Nexmo.com. Two of those mobile numbers go to phones in Israel. One of them is the same number listed for Itay Huri in the Web site registration records for v-email[dot]org; the other belongs to an Israeli citizen named Yarden Bidani. Neither individual responded to requests for comment.

The leaked database and files indicate that vDOS uses Mailgun for email management, and the secret keys needed to manage that Mailgun service were among the files stolen by my source. The data shows that vDOS support emails go to itay@huri[dot]biz, itayhuri8@gmail.com and raziel.b7@gmail.com.

LAUNDERING THE PROCEEDS FROM DDOS ATTACKS

The $618,000 in earnings documented in the vDOS leaked logs is almost certainly a conservative income figure. That’s because the vDOS service actually dates back to Sept 2012, yet the payment records are not available for purchases prior to 2014. As a result, it’s likely that this service has made its proprietors more than $1 million.

vDOS does not currently accept PayPal payments. But for several years until recently it did, and records show the proprietors of the attack service worked assiduously to launder payments for the service through a round-robin chain of PayPal accounts.

They did this because at the time PayPal was working with a team of academic researchers to identify, seize and shutter PayPal accounts that were found to be accepting funds on behalf of booter services like vDOS. Anyone interested in reading more on their success in making life harder for these booter service owners should check out my August 2015 story, Stress-Testing the Booter Services, Financially.

People running dodgy online services that violate PayPal’s terms of service generally turn to several methods to mask the true location of their PayPal Instant Payment Notification systems. Here is an interesting analysis of how popular booter services are doing so using shell corporations, link shortening services and other tricks.

Turns out, AppleJ4ck and p1st routinely recruited other forum members on Hackforums to help them launder significant sums of PayPal payments for vDOS each week.

“The paypals that the money are sent from are not verified,” AppleJ4ck says in one recruitment thread. “Most of the payments will be 200$-300$ each and I’ll do around 2-3 payments per day.”

vDos co-owner AppleJ4ck recruiting Hackforums members to help launder PayPal payments for his booter service.

vDos co-owner AppleJ4ck recruiting Hackforums members to help launder PayPal payments for his booter service.

It is apparent from the leaked vDOS logs that in July 2016 the service’s owners implemented an additional security measure for Bitcoin payments, which they accept through Coinbase. The data shows that they now use an intermediary server (45.55.55.193) to handle Coinbase traffic. When a Bitcoin payment is received, Coinbase notifies this intermediary server, not the actual vDOS servers in Bulgaria.

A server situated in the middle and hosted at a U.S.-based address from Digital Ocean then updates the database in Bulgaria, perhaps because the vDOS proprietors believed payments from the USA would attract less interest from Coinbase than huge sums traversing through Bulgaria each day. Continue reading →