More than 900,000 customers of German ISP Deutsche Telekom (DT) were knocked offline this week after their Internet routers got infected by a new variant of a computer worm known as Mirai. The malware wriggled inside the routers via a newly discovered vulnerability in a feature that allows ISPs to remotely upgrade the firmware on the devices. But the new Mirai malware turns that feature off once it infests a device, complicating DT’s cleanup and restoration efforts.

Security experts say the multi-day outage is a sign of things to come as cyber criminals continue to aggressively scour the Internet of Things (IoT) for vulnerable and poorly-secured routers, Internet-connected cameras and digital video recorders (DVRs). One enslaved, the IoT devices can be used and rented out for a variety of purposes — from conducting massive denial-of-service attacks capable of knocking large Web sites offline to helping cybercriminals stay anonymous online.

This new variant of Mirai builds on malware source code released at the end of September. That leak came a little more a week after a botnet based on Mirai was used in a record-sized attack that caused KrebsOnSecurity to go offline for several days. Since then, dozens of new Mirai botnets have emerged, all competing for a finite pool of vulnerable IoT systems that can be infected.

Until this week, all Mirai botnets scanned for the same 60+ factory default usernames and passwords used by millions of IoT devices. But the criminals behind one of the larger Mirai botnets apparently decided to add a new weapon to their arsenal, incorporating exploit code published earlier this month for a security flaw in specific routers made by Zyxel and Speedport.

These companies act as original equipment manufacturers (OEMs) that specialize in building DSL modems that ISPs then ship to customers. The vulnerability exists in communications protocols supported by the devices that ISPs can use to remotely manage all of the customer-premises routers on their network.

According to BadCyber.com, which first blogged about the emergence of the new Mirai variant, part of the problem is that Deutsche Telekom does not appear to have followed the best practice of blocking the rest of the world from remotely managing these devices as well.

“The malware itself is really friendly as it closes the vulnerability once the router is infected,” BadCyber noted. “It performs [a] command which should make the device ‘secure,’ until next reboot. The first one closes port 7547 and the second one kills the telnet service, making it really hard for the ISP to update the device remotely.” [For the Geek Factor 5 readership out there, the flaw stems from the way these routers parse incoming traffic destined for Port 7547 using communications protocols known as TR-069].

DT has been urging customers who are having trouble to briefly disconnect and then reconnect the routers, a process which wipes the malware from the device’s memory. The devices should then be able to receive a new update from DT that plugs the vulnerability.

That is, unless the new Mirai strain gets to them first. Johannes Ullrich, dean of security research at The SANS Technology Institute, said this version of Mirai aggressively scans the Internet for new victims, and that SANS’s research has shown vulnerable devices are compromised by the new Mirai variant within five to ten minutes of being plugged into the Internet.

Ullrich said the scanning activity conducted by the new Mirai variant is so aggressive that it can create hangups and crashes even for routers that are are not vulnerable to this exploit.

“Some of these devices went down because of the sheer number of incoming connections” from the new Mirai variant, Ullrich said. “They were listening on Port 7547 but were not vulnerable to this exploit and were still overloaded with the number of connections to that port.”

FEEDING THE CRIME MACHINE

Allison Nixon, director of security research at Flashpoint, said this latest Mirai variant appears to be an attempt to feed fresh victims into one of the larger and more established Mirai botnets out there today.

Nixon said she suspects this particular botnet is being rented out in discrete chunks to other cybercriminals. Her suspicions are based in part on the fact that the malware phones home to a range of some 256 Internet addresses that for months someone has purchased for the sole purpose of hosting nothing but servers used to control multiple Mirai botnets.

“The malware points to some [Internet addresses] that are in ranges which were purchased for the express purpose of running Mirai,” Nixon said. “That range does nothing but run Mirai control servers on it, and they’ve been doing it for a while now. I would say this is probably part of a commercial service because purchasing this much infrastructure is not cheap. And you generally don’t see people doing this for kicks, you see them doing it for money.”

Nixon said the criminals behind this new Mirai variant are busy subdividing their botnet — thought to be composed of several hundred thousand hacked IoT devices — among multiple, distinct control servers. This approach, she said, addresses two major concerns among cybercriminals who specialize in building botnets that are resold for use in huge distributed denial of service (DDoS) attacks.

The first is that extended DDoS attacks which leverage firepower from more bots than are necessary to take down a target host can cause the crime machine’s overall bot count to dwindle more quickly than the botnet can replenish itself with newly infected IoT devices — greatly diminishing the crime machine’s strength and earning power.

“I’ve been watching a lot of chatter in the DDoS community, and one of the topics that frequently comes up is that there are many botnets out there where the people running them don’t know each other, they’ve just purchased time on the botnet and have been assigned specific slots on it,” Nixon said. “Long attacks would end up causing the malware or infected machines to crash, and the attack and would end up killing the botnet if it was overused. Now it looks like someone has architected a response to that concern, knowing that you have to preserve bots as much as you can and not be excessive with the DDoS traffic you’re pushing.”

Nixon said dividing the Mirai botnet into smaller sections which each answer to multiple control servers also makes the overall crime machine more resistant to takedown efforts by security firms and researchers.

“This is an interesting development because a lot of the response to Mirai lately has been to find a Mirai controller and take it down,” Nixon said. “Right now, the amount of redundant infrastructure these Mirai actors have is pretty significant, and it suggests they’re trying to make their botnets more difficult to take down.”

Nixon said she worries that the aggressive Mirai takedown efforts by the security community may soon prompt the crooks to adopt far more sophisticated and resilient methods of keeping their crime machines online.

“We have to realize that the takedown option is not going to be there forever with these IoT botnets,” she said.

The San Francisco Municipal Transportation Agency (SFMTA) was hit with a ransomware attack on Friday, causing fare station terminals to carry the message, “You Hacked. ALL Data Encrypted.” Turns out, the miscreant behind this extortion attempt got hacked himself this past weekend, revealing details about other victims as well as tantalizing clues about his identity and location.

On Friday, The San Francisco Examiner reported that riders of SFMTA’s Municipal Rail or “Muni” system were greeted with handmade “Out of Service” and “Metro Free” signs on station ticket machines. The computer terminals at all Muni locations carried the “hacked” message: “Contact for key (cryptom27@yandex.com),” the message read.

The hacker in control of that email account said he had compromised thousands of computers at the SFMTA, scrambling the files on those systems with strong encryption. The files encrypted by his ransomware, he said, could only be decrypted with a special digital key, and that key would cost 100 Bitcoins, or approximately USD $73,000.

On Monday, KrebsOnSecurity was contacted by a security researcher who said he hacked this very same cryptom27@yandex.com inbox after reading a news article about the SFMTA incident. The researcher, who has asked to remain anonymous, said he compromised the extortionist’s inbox by guessing the answer to his secret question, which then allowed him to reset the attacker’s email password. A screen shot of the user profile page for cryptom27@yandex.com shows that it was tied to a backup email address, cryptom2016@yandex.com, which also was protected by the same secret question and answer.

Copies of messages shared with this author from those inboxes indicate that on Friday evening, Nov. 25, the attacker sent a message to SFMTA infrastructure manager Sean Cunningham with the following demand (the entirety of which has been trimmed for space reasons), signed with the pseudonym “Andy Saolis.”

“if You are Responsible in MUNI-RAILWAY !

All Your Computer’s/Server’s in MUNI-RAILWAY Domain Encrypted By AES 2048Bit!

We have 2000 Decryption Key !

Send 100BTC to My Bitcoin Wallet , then We Send you Decryption key For Your All Server’s HDD!!”

One hundred Bitcoins may seem like a lot, but it’s apparently not far from a usual payday for this attacker. On Nov. 20, hacked emails show that he successfully extorted 63 bitcoins (~$45,000) from a U.S.-based manufacturing firm.

The attacker appears to be in the habit of switching Bitcoin wallets randomly every few days or weeks. “For security reasons” he explained to some victims who took several days to decide whether to pay the ransom they’d been demanded. A review of more than a dozen Bitcoin wallets this criminal has used since August indicates that he has successfully extorted at least $140,000 in Bitcoin from victim organizations.

That is almost certainly a conservative estimate of his overall earnings these past few months: My source said he was unable to hack another Yandex inbox used by this attacker between August and October 2016, “w889901665@yandex.com,” and that this email address is tied to many search results for tech help forum postings from people victimized by a strain of ransomware known as Mamba.

Copies of messages shared with this author answer many questions raised by news media coverage of this attack, such as whether the SFMTA was targeted. In short: No. Here’s why.

Messages sent to the attacker’s cryptom2016@yandex.com account show a financial relationship with at least two different hosting providers. The credentials needed to manage one of those servers were also included in the attacker’s inbox in plain text, and my source shared multiple files from that server.

KrebsOnSecurity sought assistance from several security experts in making sense of the data shared by my source. Alex Holden, chief information security officer at Hold Security Inc, said the attack server appears to have been used as a staging ground to compromise new systems, and was equipped with several open-source tools to help find and infect new victims.

“It appears our attacker has been using a number of tools which enabled the scanning of large portions of the Internet and several specific targets for vulnerabilities,” Holden said. “The most common vulnerability used ‘weblogic unserialize exploit’ and especially targeted Oracle Corp. server products, including Primavera project portfolio management software.”

According to a review of email messages from the Cryptom27 accounts shared by my source, the attacker routinely offered to help victims secure their systems from other hackers for a small number of extra Bitcoins. In one case, a victim that had just forked over a 20 Bitcoin ransom seemed all too eager to pay more for tips on how to plug the security holes that got him hacked. In return, the hacker pasted a link to a Web server, and urged the victim to install a critical security patch for the company’s Java applications.

“Read this and install patch before you connect your server to internet again,” the attacker wrote, linking to this advisory that Oracle issued for a security hole that it plugged in November 2015.

In many cases, the extortionist told victims their data would be gone forever if they didn’t pay the ransom in 48 hours or less. In other instances, he threatens to increase the ransom demand with each passing day.

WHO IS ALI REZA?

The server used to launch the Oracle vulnerability scans offers tantalizing clues about the geographic location of the attacker. That server kept detailed logs about the date, time and Internet address of each login. A review of the more than 300 Internet addresses used to administer the server revealed that it has been controlled almost exclusively from Internet addresses in Iran. Another hosting account tied to this attacker says his contact number is +78234512271, which maps back to a mobile phone provider based in Russia.

But other details from the attack server indicate that the Russian phone number may be a red herring. For example, the attack server’s logs includes the Web link or Internet address of each victimized server, listing the hacked credentials and short notations apparently made next to each victim by the attacker. Google Translate had difficulty guessing which language was used in the notations, but a fair amount of searching indicates the notes are transliterated Farsi or Persian, the primary language spoken in Iran and several other parts of the Middle East.

User account names on the attack server hold other clues, with names like “Alireza,” “Mokhi.” Alireza may pertain to Ali Reza, the seventh descendant of the Islamic prophet Muhammad, or just to a very common name among Iranians, Arabs and Turks.

The targets successfully enumerated as vulnerable by the attacker’s scanning server include the username and password needed to remotely access the hacked servers, as well as the IP address (and in some cases domain name) of the victim organization. In many cases, victims appeared to use newly-registered email addresses to contact the extortionist, perhaps unaware that the intruder had already done enough reconnaissance on the victim organization to learn the identity of the company and the contact information for the victim’s IT department.

The list of victims from our extortionist shows that the SFMTA was something of an aberration. The vast majority of organizations victimized by this attacker were manufacturing and construction firms based in the United States, and most of those victims ended up paying the entire ransom demanded — generally one Bitcoin (currently USD $732) per encrypted server.

Emails from the attacker’s inbox indicate some victims managed to negotiate a lesser ransom. China Construction of America Inc., for example, paid 24 Bitcoins (~$17,500) on Sunday, Nov. 27 to decrypt some 60 servers infected with the same ransomware — after successfully haggling the attacker down from his original demand of 40 Bitcoins. Other construction firms apparently infected by ransomware attacks from this criminal include King of Prussia, Pa. based Irwin & Leighton; CDM Smith Inc. in Boston; Indianapolis-based Skillman; and the Rudolph Libbe Group, a construction consulting firm based in Walbridge, Ohio. It’s unclear whether any of these companies paid a ransom to regain access to their files.

PROTECT YOURSELF AND YOUR ORGANIZATION

The data leaked from this one actor shows how successful and lucrative ransomware attacks can be, and how often victims pay up. For its part, the SFMTA said it never never considered paying the ransom.

“We have an information technology team in place that can restore our systems and that is what they are doing,” said SFMTA spokesman Paul Rose. “Existing backup systems allowed us to get most affected computers up and running this morning, and our information technology team anticipates having the remaining computers functional in the next two days.”

As the SFMTA’s experience illustrates, having proper and regular backups of your data can save you bundles. But unsecured backups can also be encrypted by ransomware, so it’s important to ensure that backups are not connected to the computers and networks they are backing up. Examples might include securing backups in the cloud or physically storing them offline. It should be noted, however, that some instances of ransomware can lock cloud-based backups when systems are configured to continuously back up in real-time.

That last tip is among dozens offered by the Federal Bureau of Investigation, which has been warning businesses about the dangers of ransomware attacks for several years now. For more tips on how to avoid becoming the next ransomware victim, check out the FBI’s most recent advisory on ransomware.

Finally, as I hope this story shows, truthfully answering secret questions is a surefire way to get your online account hacked. Personally, I try to avoid using vital services that allow someone to reset my password if they can guess the answers to my secret questions. But in some cases — as with United Airlines’s atrocious new password system — answering secret questions is unavoidable. In cases where I’m allowed to type in the answer, I always choose a gibberish or completely unrelated answer that only I will know and that cannot be unearthed using social media or random guessing.

KrebsOnSecurity has featured multiple stories about the threat from ATM fraud devices known as “insert skimmers,” wafer-thin data theft tools made to be completely hidden inside of a cash’s machine’s card acceptance slot. For a closer look at how stealthy insert skimmers can be, it helps to see videos of these things being installed and removed. Here’s a look at promotional sales videos produced by two different ATM insert skimmer peddlers.

Traditional ATM skimmers are fraud devices made to be placed over top of the cash machine’s card acceptance slot, usually secured to the ATM with glue or double-sided tape. Increasingly, however, more financial institutions are turning to technologies that can detect when something has been affixed to the ATM. As a result, more fraudsters are selling and using insert skimming devices — which are completely hidden from view once inserted into an ATM.

The fraudster demonstrating his insert skimmer in the short video above spends the first half of the demo showing how a regular bank card can freely move in and out of the card acceptance slot while the insert skimmer is nestled inside. Toward the end of the video, the scammer retrieves the insert skimmer using what appears to be a rather crude, handmade tool thin enough to fit inside a wallet.

A sales video produced by yet another miscreant in the cybercrime underground shows an insert skimmer being installed and removed from a motorized card acceptance slot that has been fully removed from an ATM so that the fraud device can be seen even while it is inserted.

In a typical setup, insert skimmers capture payment card data from the magnetic stripe on the backs of cards inserted into a hacked ATM, while a pinhole spy camera hidden above or beside the PIN pad records time-stamped video of cardholders entering their PINs. The data allows thieves to fabricate new cards and use PINs to withdraw cash from victim accounts.

Covering the PIN pad with your hand blocks any hidden camera from capturing your PIN — and hidden cameras are used on the vast majority of the more than three dozen ATM skimming incidents that I’ve covered here. Shockingly, few people bother to take this simple and effective step, as detailed in this skimmer tale from 2012, wherein I obtained hours worth of video seized from two ATM skimming operations and saw customer after customer walk up, insert their cards and punch in their digits — all in the clear.

Once you understand how stealthy these ATM fraud devices are, it’s difficult to use a cash machine without wondering whether the thing is already hacked. The truth is most of us probably have a better chance of getting physically mugged after withdrawing cash than encountering a skimmer in real life. However, here are a few steps we can all take to minimize the success of skimmer gangs.

-Cover the PIN pad while you enter your PIN.

-Keep your wits about you when you’re at the ATM, and avoid dodgy-looking and standalone cash machines in low-lit areas, if possible.

-Stick to ATMs that are physically installed in a bank. Stand-alone ATMs are usually easier for thieves to hack into.

-Be especially vigilant when withdrawing cash on the weekends; thieves tend to install skimming devices on a weekend — when they know the bank won’t be open again for more than 24 hours.

-Keep a close eye on your bank statements, and dispute any unauthorized charges or withdrawals immediately.

If you liked this piece and want to learn more about skimming devices, check out my series All About Skimmers.

Hackers of all stripes looking to test their mettle can now legally hone their cyber skills, tools and weaponry against any Web property operated by the U.S. Department of Defense (DoD), according to a new military-wide policy for reporting and fixing security vulnerabilities.

Security researchers are often reluctant to report programming flaws or security holes they’ve stumbled upon for fear that the vulnerable organization might instead decide to shoot the messenger and pursue hacking charges.

But on Nov. 21, the DoD sought to clear up any ambiguity on that front for the military’s substantial online presence, creating both a centralized place to report cybersecurity flaws across the dot-mil space as well as a legal safe harbor (and the prospect of public recognition) for researchers who abide by a few ground rules.

The DoD said it would “deal in good faith” with researchers “who discover, test, and submit vulnerabilities or indicators of vulnerabilities in accordance with these guidelines:

“Your activities are limited exclusively to –
(1) Testing to detect a vulnerability or identify an indicator related to a vulnerability; or
(2) Sharing with, or receiving from, DoD information about a vulnerability or an indicator related to a vulnerability.”

The Department of Defense also issued the following ten commandments for demonstrating compliance with its policy:

1. You do no harm and do not exploit any vulnerability beyond the minimal amount of testing required to prove that a vulnerability exists or to identify an indicator related to a vulnerability.
2. You avoid intentionally accessing the content of any communications, data, or information transiting or stored on DoD information system(s) – except to the extent that the information is directly related to a vulnerability and the access is necessary to prove that the vulnerability exists.
3. You do not exfiltrate any data under any circumstances.
4. You do not intentionally compromise the privacy or safety of DoD personnel (e.g. civilian employees or military members), or any third parties.
5. You do not intentionally compromise the intellectual property or other commercial or financial interests of any DoD personnel or entities, or any third parties.
6. You do not publicly disclose any details of the vulnerability, indicator of vulnerability, or the content of information rendered available by a vulnerability, except upon receiving explicit written authorization from DoD.
7. You do not conduct denial of service testing.
8. You do not conduct social engineering, including spear phishing, of DoD personnel or contractors.
9. You do not submit a high-volume of low-quality reports.
10. If at any point you are uncertain whether to continue testing, please engage with our team.

In return, the DoD said it commits to acknowledging receipt of a report within three business days, and that it will work to confirm the existence of the vulnerability to the researcher and keep the researcher informed of any remediation underway. There are some restrictions, however. For example, researchers who report vulnerabilities will be expected to refrain from publicly disclosing their findings unless and until the DoD provides written consent that it’s okay to do so.

“We want researchers to be recognized publicly for their contributions, if that is the researcher’s desire,” the DoD stated. “We will seek to allow researchers to be publicly recognized whenever possible. However, public disclosure of vulnerabilities will only be authorized at the express written consent of DoD.”

The DoD said if it couldn’t immediately fix or publicly acknowledge reported vulnerabilities, it might be because doing so could have life-or-death consequences for service members.

“Many DoD technologies are deployed in combat zones and, to varying degrees, support ongoing military operations; the proper functioning of DoD systems and applications can have a life-or-death impact on Service members and international allies and partners of the United States,” the agency observed. “DoD must take extra care while investigating the impact of vulnerabilities and providing a fix, so we ask your patience during this period.”

HACK THE ARMY

The Defense Department made the announcement via Hackerone.com, a company that helps organizations build and manage vulnerability reporting policies. HackerOne also helps customers build out “bug bounty” programs that remunerate and recognize researchers who report security flaws.

HackerOne currently is coordinating an upcoming bug bounty program called “Hack the Army,” in which some 500 qualifying contestants can earn cash rewards for finding and reporting cybersecurity weaknesses in the Army’s various online properties (incidentally, Hack the Army runs from Nov. 30 through Dec. 21, 2016, and interested/eligible hackers have until Nov. 28, at 17:00 EST to apply for a shot at one of those 500 spots).

Alex Rice, HackerOne’s co-founder and chief technology officer, said most organizations don’t have an official policy about how they will respond to reports about cybersecurity weaknesses and liabilities, and that the absence of such a policy often discourages researchers from reporting serious security holes.

“The default is terribly unfriendly to researchers,” Rice said. “The Computer Fraud and Abuse Act (CFAA) allows almost any company to go after researchers as hackers, and this happened far too many times. What this does is carve out a safe harbor from the CFAA, and begin to create a safe place that is really powerful and important.”

Rice said HackerOne last year took an inventory of vulnerability disclosure policies at the Global Forbes 2000 list of companies, and found that only six percent of them had published guidelines.

“You cannot run an effective public vulnerability disclosure program or a bug bounty program without having competent security professionals internally,” Rice said. “The problem is, the vast majority of organizations don’t have that.”

And when you start asking people to find and report gaps in your cybersecurity armor, you’d better be ready for them to do just that, said Jeremiah Grossman, chief security of strategy at anti-malware firm SentinelOne.

“I’ve seen people try to launch these vulnerability disclosure programs and then fail spectacularly because they don’t have the resources to handle the response,” said Grossman, who also serves on the advisory board for Bugcrowd — one of HackerOne’s competitors. “When you’re really mature in security, and not before then, is about the right time for a bug bounty program. If the organization can handle one to five vulnerabilities reported each month and can fix each of those in a few days, then they’re probably ready.”

Rice said one reason he’s so excited about bug bounty programs is that they offer would-be security professionals a way to demonstrate their skills in a safe and controlled environment.

“If you’re a security professional looking to challenge yourself and you skills, there are very few real world opportunities to do that, to test your mettle and improve,” Rice said. “But that real-world experience is so unbelievably critical in this industry, and we need to be creating more opportunities for people to improve that. The more we can do that and share what we learn out of it, the more we can raise the talent and education of security professionals worldwide.”

Hardly a week goes by when I don’t hear from a young or career-changing reader asking for advice about how to carve out a living in cybersecurity. This happened so often that I created an entire category of posts on this topic: How to Break Into Security. I’ll be revisiting that series soon, but for the time being I want to encourage anyone interested in building their skills through legal hacking to consider creating relationships with companies that have already sanctioned — and in many cases financially reward — such activity.

For starters, Bugcrowd has a nice list of bug bounty and disclosure programs from across the Web, broken down according to whether they offer various benefits such as financial reward, swag or public recognition. Hackerone maintains a searchable directory of security contacts and vulnerability reporting policies at various corporations.

Internet infrastructure giant Akamai last week released a special State of the Internet report. Normally, the quarterly accounting of noteworthy changes in distributed denial-of-service (DDoS) attacks doesn’t delve into attacks on specific customers. But this latest Akamai report makes an exception in describing in great detail the record-sized attack against KrebsOnSecurity.com in September, the largest such assault it has ever mitigated.

“The attacks made international headlines and were also covered in depth by Brian Krebs himself,” Akamai said in its report, explaining one reason for the exception. “The same data we’ve shared here was made available to Krebs for his own reporting and we received permission to name him and his site in this report. Brian Krebs is a security blogger and reporter who does in-depth research and analysis of cybercrime throughout the world, with a recent emphasis on DDoS. His reporting exposed a stressor site called vDOS and the security firm BackConnect Inc., which made him the target of a series of large DDoS attacks starting September 15, 2016.”

Akamai said so-called “booter” or “stresser” DDoS-for-hire services that sell attacks capable of knocking Web sites offline continue to account for a large portion of the attack traffic in mega attacks. According to Akamai, most of the traffic from those mega attacks in Q3 2016 were thanks to Mirai — the now open-source malware family that was used to coordinate the attack on this site in September and a separate assault against infrastructure provider Dyn in October.

Akamai said the attack on Sept. 20 was launched by just 24,000 systems infected with Mirai, mostly hacked Internet of Things (IoT) devices such as digital video recorders and security cameras.

“The first quarter of 2016 marked a high point in the number of attacks peaking at more than 100 Gbps,” Akamai stated in its report. “This trend was matched in Q3 2016, with another 19 mega attacks. It’s interesting that while the overall number of attacks fell by 8% quarter over quarter, the number of large attacks, as well as the size of the biggest attacks, grew significantly.”

As detailed here in several previous posts, KrebsOnSecurity.com was a pro-bono customer of Akamai, beginning in August 2012 with Prolexic before Akamai acquired them. Akamai mentions this as well in explaining its decision to terminate our pro-bono arrangement. KrebsOnSecurity is now behind Google‘s Project Shield, a free program run by Google to help protect journalists and dissidents from online censorship.

“Almost as soon as the site was on the Prolexic network, it was hit by a trio of attacks based on the Dirt Jumper DDoS tookit,” Akamai wrote of this site. “Those attacks marked the start of hundreds of attacks that were mitigated on the routed platform.”

In total, Akamai found, this site received 269 attacks in the little more than four years it was on the Prolexic/Akamai network.

“During that time, there were a dozen mega attacks peaking at over 100 Gbps,” the company wrote. “The first happened in December 2013, the second in February 2014, and the third in August 2015. In 2016, the size of attacks accelerated dramatically, with four mega attacks happening between March and August, while five attacks occurred in September, ranging from 123 to 623 Gbps. An observant reader can probably correlate clumps of attacks to specific stories covered by Krebs. Reporting on the dark side of cybersecurity draws attention from people and organizations who are not afraid of using DDoS attacks to silence their detractors.”

In case any trenchant observant readers wish to attempt that, I’ve published a spreadsheet here (in .CSV format) which lists the date, duration, size and type of attack used in DDoS campaigns against KrebsOnSecurity.com over the past four years. Although 269 attacks over four years works out to an average of just one attack roughly every five days, both the frequency and intensity of these attacks have increased substantially over the past four years as illustrated by the graphic above.

“The magnitude of the attacks seen during the final week were significantly larger than the majority of attacks Akamai sees on a regular basis,” Akamai reports. “In fact, while the attack on September 20 was the largest attack ever mitigated by Akamai, the attack on September 22 would have qualified for the record at any other time, peaking at 555 Gbps.”

Akamai found that the 3rd quarter of 2016 marks a full year with China as the top source country for DDoS attacks, with just under 30 percent of attack traffic in Q3 2016. The company notes that this metric doesn’t count UDP-based attacks – such as amplification and reflection attacks — due to the ease with which the sources of the attacks can be spoofed and could create significant distortion of the data.

“More importantly, the proportion of traffic from China has been reduced by 56%, which had a significant effect on the overall attack count and led to the 8% drop in attacks seen this quarter,” Akamai reported. The U.S., U.K., France, and Brazil round out the remaining top five source countries.”

A copy of Akamai’s Q3 2016 State of the Internet report is available here.