SMS text messages were already the weakest link securing just about anything online, mainly because there are tens of thousands of people (many of them low-paid mobile store employees) who can be tricked or bribed into swapping control over a mobile phone number to someone else. Now we’re learning about an entire ecosystem of companies that anyone could use to silently intercept text messages intended for other mobile users.

Security researcher “Lucky225” worked with Vice.com’s Joseph Cox to intercept Cox’s incoming text messages with his permission. Lucky225 showed how anyone could do the same after creating an account at a service called Sakari, a company that helps celebrities and businesses do SMS marketing and mass messaging.

The “how they did it” was sickeningly simple. It cost just $16, and there was precious little to prevent someone from stealing your text messages without your knowledge. Cox writes:

Sakari offers a free trial to anyone wishing to see what the company’s dashboard looks like. The cheapest plan, which allows customers to add a phone number they want to send and receive texts as, is where the $16 goes. Lucky225 provided Motherboard with screenshots of Sakari’s interface, which show a red “+” symbol where users can add a number.

While adding a number, Sakari provides the Letter of Authorization for the user to sign. Sakari’s LOA says that the user should not conduct any unlawful, harassing, or inappropriate behavior with the text messaging service and phone number.

But as Lucky225 showed, a user can just sign up with someone else’s number and receive their text messages instead.

Lucky told KrebsOnSecurity that Sakari has since taken steps to block its service for being used with mobile telephone numbers. But he said Sakari is just one part of a much larger, unregulated industry that can be used to hijack SMS messages for many phone numbers.

“It’s not a Sakari thing,” Lucky225 replied when first approached for more details. “It’s an industry-wide thing. There are many of these ‘SMS enablement’ providers.”

The most common way thieves hijack SMS messages these days involves “sim swapping,” a crime that involves bribing or tricking employees at wireless phone companies into modifying customer account information.

In a SIM swap, the attackers redirect the target’s phone number to a device they control, and then can intercept the target’s incoming SMS messages and phone calls. From there, the attacker can reset the password of any account which uses that phone number for password reset links.

But the attacks Lucky225 has been demonstrating merely require customers of any number of firms to sign a sworn “letter of authorization” or LOA stating that they indeed do have the authority to act on behalf of the owner of the targeted number.

Allison Nixon is chief research officer at Unit221B, a New York City-based cyber investigations firm. An expert on SIM-swapping attacks who’s been quoted quite a bit on this blog, Nixon said she also had Lucky225 test his interception tricks on her mobile phone, only to watch her incoming SMS messages show up on his burner phone.

“This basically means the only thing standing between anyone and the equivalent of a SIM swap is a forged LOA,” Nixon said. “And the ‘fix’ put in seems to be temporary in nature.”

The interception method that Lucky225 described is still dangerously exposed by a number of systemic weaknesses in the global SMS network, he said.

Most large and legacy telecommunications providers validate transfer requests related to their customers by consulting NPAC, or the Number Portability Administration Center. When customers want to move their phone numbers — mobile or otherwise — that request is routed through NPAC to the customer’s carrier.

That change request carries what’s known as an ALT-SPID, which is a four-digit number that enables NPAC to identify the telecommunications company currently providing service to the customer. More importantly, as part of this process no changes can happen unless the customer’s carrier has verified the changes with the existing customer.

But Lucky225 said the class of SMS interception he’s been testing targets a series of authentication weaknesses tied to a system developed by NetNumber, a private company in Lowell, Mass. NetNumber developed its own proprietary system for mapping telecommunications providers that is used by Sakari and an entire industry of similar firms.

NetNumber developed its six-digit ALT SPIDs (NetNumber IDs) to better organize and track communications service providers that were all using other numbering systems (and differing numbers of digits). But NetNumber also works directly with dozens of voice-over-IP or Internet-based phone companies which do not play by the same regulatory rules that apply to legacy telecommunications providers.

“There are many VoIP providers that offer ‘off net’ ‘text enablement’,” Lucky225 explained. “Companies such as ZipWhip that promise to let you ‘Text enable your existing business phone number’ so that customers can text your main business line whether it be VoIP, toll-free or a landline number.”

As Lucky225 wrote in his comprehensive Medium article, there are a plethora of wholesale VoIP providers that let you become a reseller with little to no verification, many of them allow blanket Letters of Authorization (LOAs), where you as the reseller promise that you have an LOA on file for any number you want to text enable for your resellers or end-users.

“In essence, once you have a reseller account with these VoIP wholesalers you can change the Net Number ID of any phone number to your wholesale provider’s NNID and begin receiving SMS text messages with virtually no authentication whatsoever. No SIM Swap, SS7 attacks, or port outs needed — just type the target’s phone number in a text box and hit submit and within minutes you can start receiving SMS text messages for them. They won’t even be alerted that anything has happened as their voice & data services will continue to work as usual. Surprisingly, despite the fact that I publicly disclosed this in 2018, nothing has been done to stop this relatively unsophisticated attack.”

NetNumber declined to comment on the record, but instead referred to a statement from the CTIA, a trade association representing the wireless industry, which reads:

“After being made aware of this potential threat, we worked immediately to investigate it, and took precautionary measures. Since that time, no carrier has been able to replicate it. We have no indication of any malicious activity involving the potential threat or that any customers were impacted. Consumer privacy and safety is our top priority, and we will continue to investigate this matter.”

Lucky225 told KrebsOnSecurity many of the major mobile companies have moved to ensure none of their customers can be affected by changes requested through NetNumber or its partners. But he suspects some of the smaller wired and wireless telecommunications firms may still be vulnerable.

“I’m pretty sure it’s only the big carriers that they’re protecting now,” he said. “But there’s just so much we don’t know about what they patched because everyone is being so tight lipped about this right now.”

Nixon said it’s time for federal regulators to step up and protect consumers.

“Its clear this is a lot of foundational infrastructure mucky muck and some fundamental changes are going to need to happen here,” she said. “Regulators really need to get involved.”

WHAT CAN YOU DO?

Given the potentially broad impact of fraudsters abusing this and other weaknesses in the vast mobile ecosystem to completely subvert the security of SMS based communications and multi-factor authentication, it’s probably a good idea to rethink your relationship to your phone number. It’s now plainer than ever how foolish it is to trust SMS for anything.

My advice has long been to remove phone numbers from your online accounts wherever you can, and avoid selecting SMS or phone calls for second factor or one-time codes. Phone numbers were never designed to be identity documents, but that’s effectively what they’ve become. It’s time we stopped letting everyone treat them that way.

Any online accounts that you value should be secured with a unique and strong password, as well the most robust form of multi-factor authentication available. Usually, this is a mobile app like Authy or Google Authenticator that generates a one-time code. Some sites like Twitter and Facebook now support even more robust options — such as physical security keys.

Removing your phone number may be even more important for any email accounts you may have. Sign up with any service online, and it will almost certainly require you to supply an email address. In nearly all cases, the person who is in control of that address can reset the password of any associated services or accounts– merely by requesting a password reset email.

Unfortunately, many email providers still let users reset their account passwords by having a link sent via text to the phone number on file for the account. So remove the phone number as a backup for your email account, and ensure a more robust second factor is selected for all available account recovery options.

Here’s the thing: Most online services require users to supply a mobile phone number when setting up the account, but do not require the number to remain associated with the account after it is established. I advise readers to remove their phone numbers from accounts wherever possible, and to take advantage of a mobile app to generate any one-time codes for multifactor authentication.

A little over a year ago, the FBI and law enforcement partners overseas seized WeLeakInfo[.]com, a wildly popular service that sold access to more than 12 billion usernames and passwords stolen from thousands of hacked websites. In an ironic turn of events, a lapsed domain registration tied to WeLeakInfo let someone plunder and publish account data on 24,000 customers who paid to access the service with a credit card.

For several years, WeLeakInfo was the largest of several services selling access to hacked passwords. Prosecutors said it had indexed, searchable information from more than 10,000 data breaches containing over 12 billion indexed records — including names, email addresses, usernames, phone numbers, and passwords for online accounts.

For a small fee, you could enter an email address and see every password ever associated with that address in a previous breach. Or the reverse — show me all the email accounts that ever used a specific password (see screenshot above). It was a fantastic tool for launching targeted attacks against people, and that’s exactly how the service was viewed by many of its customers.

Now, nearly 24,000 WeLeakInfo’s customers are finding that the personal and payment data they shared with WeLeakInfo over its five-year-run has been leaked online.

In a post on the database leaking forum Raidforums, a regular contributor using the handle “pompompurin” said he stole the WeLeakInfo payment logs and other data after noticing the domain wli[.]design was no longer listed as registered.

“Long story short: FBI let one of weleakinfo’s domains expire that they used for the emails/payments,” pompompurin wrote. “I registered that domain, & was able to [password] reset the stripe.com account & get all the Data. [It’s] only from people that used stripe.com to checkout. If you used paypal or [bitcoin] ur all good.”

Cyber threat intelligence firm Flashpoint obtained a copy of the data leaked by pompompurin, and said it includes partial credit card data, email addresses, full names, IP addresses, browser user agent string data, physical addresses, phone numbers, and amount paid. One forum member commented that they found their own payment data in the logs.

According to DomainTools [an advertiser on this site] Wli[.]design was registered on Aug. 24, 2016 with the domain registrar Dynadot. On March 12, the domain was moved to another registrar — Namecheap.

Pompompurin released several screenshots of himself logged in to the WeLeakInfo account at stripe.com, an online payment processor. Under “management and ownership” was listed a Gerald Murphy from Fintona, U.K.

Shortly after WeLeakInfo’s domain was seized by authorities in Jan. 2020, the U.K.’s National Crime Agency (NCA) arrested two individuals in connection with the service, including a 22-year-old from Fintona.

PLENTY OF TIME FOR OPSEC MISTAKES

It’s been a tough few months for denizens of various hacking forums, which are finding themselves on the defensive end of a great many attacks testing the security of their aliases and operational security lately. Over the past few weeks three of the longest running and most venerated Russian-language online forums serving thousands of experienced cybercriminals have been hacked.

In two of the intrusions (against the Russian hacking forums “Mazafaka” and “Verified”) — the attackers made off with the forums’ user databases, including email and Internet addresses and hashed passwords.

“Members of all three forums are worried the incidents could serve as a virtual Rosetta Stone for connecting the real-life identities of the same users across multiple crime forums,” a recent story here explained.

An exposure of 15 years worth of user data from a forum like Mazafaka is a big risk for registrants because investigators often can use common registration details to connect specific individuals who might have used multiple hacker handles over the years.

Many of the domains from the email addresses listed in the Maza dump date to the early 2000s, back when budding cybercriminals typically took fewer precautions to obfuscate or separate the myriad connections to their real-life identities online.

The biggest potential gold mine for de-anonymizing Maza members is the leak of user numbers for ICQ, an instant messaging service formerly owned by AOL that was widely used by cybercrime forum members up until around 2010. That’s about when AOL sold the platform in 2010 to Russian investor DST for $187.5 million.

Back then, people often associated their ICQ numbers to different interests, pursuits and commerce tied to their real life identities. In many cases, these associations are on public, Russian language forums, such as discussion sites on topics like cars, music or programming.

In a common inadvertent exposure, a cybercriminal happens to make an innocuous post 15 years ago to a now-defunct Russian-language automobile forum.

That post, preserved in perpetuity by sites like archive.org, includes an ICQ number and says there’s a guy named Sergey in Vladivostok who’s selling his car. And the profile link on the auto forum leads to another now-defunct but still-archived personal site for Sergey.

Interestingly, services like WeLeakInfo can just as easily be used against cybercriminals as by them. For example, it’s likely that the database for the automobile forum where Sergey posted got compromised at some point and is for sale on sites like WeLeakInfo (there are active competitors).

Ditto for any other forum where Sergey used the same email address or password. When researchers start finding password re-use across multiple email addresses that all follow a pattern, it becomes much easier to tie Sergey from Vladivostok to his cybercriminal and real-life identities.

On the off chance you were looking for more security to-dos from Microsoft today…the company released software updates to plug more than 82 security flaws in Windows and other supported software. Ten of these earned Microsoft’s “critical” rating, meaning they can be exploited by malware or miscreants with little or no help from users.

Top of the heap this month (apart from the ongoing, global Exchange Server mass-compromise) is a patch for an Internet Explorer bug that is seeing active exploitation. The IE weakness — CVE-2021-26411 — affects both IE11 and newer EdgeHTML-based versions, and it allows attackers to run a file of their choice by getting you to view a hacked or malicious website in IE.

The IE flaw is tied to a vulnerability that was publicly disclosed in early February by researchers at ENKI who claim it was one of those used in a recent campaign by nation-state actors to target security researchers. In the ENKI blog post, the researchers said they will publish proof-of-concept (PoC) details after the bug has been patched.

“As we’ve seen in the past, once PoC details become publicly available, attackers quickly incorporate those PoCs into their attack toolkits,” said Satnam Narang, staff research engineer at Tenable. “We strongly encourage all organizations that rely on Internet Explorer and Microsoft Edge (EdgeHTML-Based) to apply these patches as soon as possible.”

This is probably a good place to quote Ghacks.net’s Martin Brinkman: This is the last patch hurrah for the legacy Microsoft Edge web browser, which is being retired by Microsoft.

For the second month in a row, Microsoft has patched scary flaws in the DNS servers on Windows Server 2008 through 2019 versions that could be used to remotely install software of the attacker’s choice. All five of the DNS bugs quashed in today’s patch batch earned a CVSS Score (danger metric) of 9.8 — almost as bad as it gets.

“There is the outside chance this could be wormable between DNS servers,” warned Trend Micro’s Dustin Childs.

As mentioned above, hundreds of thousands of organizations are in the midst dealing with a security nightmare after having their Exchange Server and Outlook Web Access (OWA) hacked and retrofitted with a backdoor. If an organization you know has been affected by this attack, please have them check with the new victim notification website mentioned in today’s story.

Susan Bradley over at Askwoody.com says “nothing in the March security updates (besides the Exchange ones released last week) is causing me to want to urge you to go running to your machines and patch at this time.” I’d concur, unless of course you cruise the web with older Microsoft browsers.

It’s a good idea for Windows users to get in the habit of updating at least once a month, but for regular users (read: not enterprises) it’s usually safe to wait a few days until after the patches are released, so that Microsoft has time to iron out any kinks in the new armor.

But before you update, please make sure you have backed up your system and/or important files. It’s not uncommon for a Windows update package to hose one’s system or prevent it from booting properly, and some updates have been known to erase or corrupt files.

So do yourself a favor and backup before installing any patches. Windows 10 even has some built-in tools to help you do that, either on a per-file/folder basis or by making a complete and bootable copy of your hard drive all at once.

And if you wish to ensure Windows has been set to pause updating so you can back up your files and/or system before the operating system decides to reboot and install patches on its own schedule, see this guide.

As always, if you experience glitches or problems installing any of these patches this month, please consider leaving a comment about it below; there’s a better-than-even chance other readers have experienced the same and may chime in here with some helpful tips.

Additional reading:

Martin Brinkman’s always comprehensive take.

The SANS Internet Storm Center no-frills breakdown of the fixes.

 

Globally, hundreds of thousand of organizations running Exchange email servers from Microsoft just got mass-hacked, including at least 30,000 victims in the United States. Each hacked server has been retrofitted with a “web shell” backdoor that gives the bad guys total, remote control, the ability to read all email, and easy access to the victim’s other computers. Researchers are now racing to identify, alert and help victims, and hopefully prevent further mayhem.

On Mar. 5, KrebsOnSecurity broke the news that at least 30,000 organizations and hundreds of thousands globally had been hacked. The same sources who shared those figures say the victim list has grown considerably since then, with many victims compromised by multiple cybercrime groups.

Security experts are now trying to alert and assist these victims before malicious hackers launch what many refer to with a mix of dread and anticipation as “Stage 2,” when the bad guys revisit all these hacked servers and seed them with ransomware or else additional hacking tools for crawling even deeper into victim networks.

But that rescue effort has been stymied by the sheer volume of attacks on these Exchange vulnerabilities, and by the number of apparently distinct hacking groups that are vying for control over vulnerable systems.

A security expert who has briefed federal and military advisors on the threat says many victims appear to have more than one type of backdoor installed. Some victims had three of these web shells installed. One was pelted with eight distinct backdoors. This initially caused a major overcount of potential victims, and required a great deal of de-duping various victim lists.

The source, who spoke on condition of anonymity, said many in the cybersecurity community recently saw a large spike in attacks on thousands of Exchange servers that was later linked to a profit-motivated cybercriminal group.

“What we thought was Stage 2 actually was one criminal group hijacking like 10,000 exchange servers,” said one source who’s briefed U.S. national security advisors on the outbreak.

On Mar. 2, when Microsoft released updates to plug the four Exchange flaws being attacked, it attributed the hacking activity to a previously unidentified Chinese cyber espionage group it called “Hafnium.” Microsoft said Hafnium had been using the Exchange flaws to conduct a series of low-and-slow attacks against specific strategic targets, such as non-governmental organization (NGOs) and think tanks.

But by Feb. 26, that relatively stealthy activity was morphing into the indiscriminate mass-exploitation of all vulnerable Exchange servers. That means even Exchange users that patched the same day Microsoft released security updates may have had servers seeded with backdoors.

Many experts who spoke to KrebsOnSecurity said they believe different cybercriminal groups somehow learned of Microsoft’s plans to ship fixes for the Exchange flaws a week earlier than they’d hoped (Microsoft originally targeted today, Patch Tuesday, as the release date).

The vulnerability scanning activity also ramped up markedly after Microsoft released its updates on Mar. 2. Security researchers love to tear apart patches for clues about the underlying security holes, and one major concern is that various cybercriminal groups may have already worked out how to exploit the flaws independently.

AVERTING MASS-RANSOMWARE

Security experts now are desperately trying to reach tens of thousands of victim organizations with a single message: Whether you have patched yet or have been hacked, backup any data stored on those servers immediately.

Every source I’ve spoken with about this incident says they fully expect profit-motivated cybercriminals to pounce on victims by mass-deploying ransomware. Given that so many groups now have backdoor web shells installed, it would be trivial to unleash ransomware on the lot of them in one go. Also, compromised Exchange servers can be a virtual doorway into the rest of the victim’s network.

“With the number of different threat actors dropping [web] shells on servers increasing, ransomware is inevitable,” said Allison Nixon, chief research officer at Unit221B, a New York City-based cyber investigations firm.

So far there are no signs of victims of this mass-hack being ransomed. But that may well change if the exploit code used to break into these vulnerable Exchange servers goes public. And nobody I’ve interviewed seems to think working exploit code is going to stay unpublished for much longer.

When that happens, the exploits will get folded into publicly available exploit testing kits, effectively making it simple for any attacker to find and compromise a decent number of victims who haven’t already patched.

CHECK MY OWA

Nixon is part of a group of security industry leaders who are contributing data and time to a new victim notification platform online called Check My OWA (Outlook Web Access, the Internet-facing Web component of Exchange Server machines).

Perhaps it’s better to call it a self-notification service that is operated from Unit221B’s own web site. It draws on tens of thousands of data points that various ISPs and hosting firms have tied to victims around the world who are likely compromised by the backdoor shells. The data comes from large networks watching the sources and targets of mass-scans for vulnerable Exchange servers.

“Our goal is to motivate people who we might otherwise have never been able to contact,” Nixon said. “My hope is if this site can get out there, then there’s a chance some victim companies are notified and take action or can get attention.”

Enter an email address at Check My OWA, and if that address matches a domain name for a victim organization, that email address will get a notice.

If the email’s domain name (anything to the right of the @ sign) is detected in their database, the site will send that user an email stating that is has observed the email domain in a list of targeted domains.

“Malicious actors were able to successfully compromise, and some of this information suggested they may have been able to install a webshell on an Exchange server associated with this domain,” reads one of the messages to victims. “We strongly recommend saving an offline backup of your Exchange server’s emails immediately, and refer back to the site for additional information on patching and remediation.”

Other Exchange users may see this message:

“We have observed your e-mail domain appears in our list of domains the malicious actors were able to successfully compromise, and some of this information suggested they may have been able to install a webshell on an Exchange server associated with this domain,” is another message the site may return. We strongly recommend saving an offline backup of your Exchange server’s emails immediately, and refer back to the site for additional information on patching and remediation.”

Nixon said Exchange users can save themselves a potentially nightmarish scenario if they just back up any affected systems now. And given the number of adversaries currently attacking still-unpatched Exchange systems, there is almost no way this won’t end in disaster for at least some victims.

“There are researchers running honeypots to [attract] attacks from different groups, and those honeypots are getting shelled left and right,” she said. “The sooner they can run a backup, the better. This can help save a lot of heartache.”

Oh, and one more important thing: You’ll want to keep any backups disconnected from everything. Ransomware has a tendency to infect everything it can, so make sure at least one backup is stored completely offline.

“Just disconnect them from a computer, put them in a safe place and pray you don’t need them,” Nixon said.

Sometimes when a complex story takes us by surprise or knocks us back on our heels, it pays to revisit the events in a somewhat linear fashion. Here’s a brief timeline of what we know leading up to last week’s mass-hack, when hundreds of thousands of Microsoft Exchange Server systems got compromised and seeded with a powerful backdoor Trojan horse program.

When did Microsoft find out about attacks on previously unknown vulnerabilities in Exchange?

Pressed for a date when it first became aware of the problem, Microsoft told KrebsOnSecurity it was initially notified “in early January.” So far the earliest known report came on Jan. 5, from a principal security researcher for security testing firm DEVCOR who goes by the handle “Orange Tsai.” DEVCOR is credited with reporting two of the four Exchange flaws that Microsoft patched on Mar. 2.

Reston, Va.-based Volexity first identified attacks on the flaws on Jan. 6, and officially informed Microsoft about it on Feb. 2. Volexity now says it can see attack traffic going back to Jan. 3. Microsoft credits Volexity with reporting the same two Exchange flaws as DEVCOR.

Danish security firm Dubex says it first saw clients hit on Jan. 18, and reported their incident response findings to Microsoft on Jan. 27.

In a blog post on their discovery, Please Leave an Exploit After the Beep, Dubex said the victims it investigated in January had a “web shell” backdoor installed via the “unifying messaging” module, a component of Exchange that allows an organization to store voicemail and faxes along with emails, calendars, and contacts in users’ mailboxes.

“A unified messaging server also allows users access to voicemail features via smartphones, Microsoft Outlook and Outlook Web App,” Dubex wrote. “Most users and IT departments manage their voicemail separately from their email, and voicemail and email exist as separate inboxes hosted on separate servers. Unified Messaging offers an integrated store for all messages and access to content through the computer and the telephone.”

Dubex says Microsoft “escalated” their issue on Feb. 8, but never confirmed the zero-day with Dubex prior to the emergency patch plea on Mar. 2. “We never got a ‘real’ confirmation of the zero-day before the patch was released,” said Dubex’s Chief Technology Officer Jacob Herbst.

How long have the vulnerabilities exploited here been around?

On Mar. 2, Microsoft patched four flaws in Exchange Server 2013 through 2019. Exchange Server 2010 is no longer supported, but the software giant made a “defense in depth” exception and gave Server 2010 users a freebie patch, too. That means the vulnerabilities the attackers exploited have been in the Microsoft Exchange Server code base for more than ten years.

The timeline also means Microsoft had almost two months to push out the patch it ultimately shipped Mar. 2, or else help hundreds of thousands of Exchange customers mitigate the threat from this flaw before attackers started exploiting it indiscriminately.

Here’s a rough timeline as we know it so far:

• Jan. 5: DEVCOR alerts Microsoft of its findings.
• Jan. 6: Volexity spots attacks that use unknown vulnerabilities in Exchange.
• Jan. 8: DEVCOR reports Microsoft had reproduced the problems and verified their findings.
• Jan. 11: DEVCOR snags proxylogon.com, a domain now used to explain its vulnerability discovery process.
• Jan. 27: Dubex alerts Microsoft about attacks on a new Exchange flaw.
• Jan. 29: Trend Micro publishes a blog post about “Chopper” web shells being dropped via Exchange flaws.
• Feb. 2: Volexity warns Microsoft about active attacks on previously unknown Exchange vulnerabilities.
• Feb. 8: Microsoft tells Dubex it has “escalated” its report internally.
• Feb. 18: Microsoft confirms with DEVCOR a target date of Mar. 9 (tomorrow) for publishing security updates for the Exchange flaws. That is the second Tuesday of the month — a.k.a. “Patch Tuesday,” when Microsoft releases monthly security updates (and yes that means check back here tomorrow for the always riveting Patch Tuesday roundup).
• Feb. 26-27: Targeted exploitation gradually turns into a global mass-scan; attackers start rapidly backdooring vulnerable servers.
• Mar. 2: A week earlier than previously planned, Microsoft releases updates to plug 4 zero-day flaws.
• Mar. 3: Tens of thousands of Exchange servers compromised worldwide, with thousands more servers getting freshly hacked each hour.
• Mar. 5: KrebsOnSecurity breaks the news that at least 30,000 organizations in the U.S. — and hundreds of thousands worldwide — now have backdoors installed.
• Mar. 5: Wired.com confirms the reported number of victims. White House makes statement expressing concern over the size of the attack. Former CISA head Chris Krebs tweets the numbers are bigger than what’s been reported.
• Mar. 6: CISA says it is aware of “widespread domestic and international exploitation of Microsoft Exchange Server flaws.”
• Mar. 7-Present: Security experts continue effort to notify victims, coordinate remediation, and remain vigilant for “Stage 2” of this attack (further exploitation of already-compromised servers).