Microsoft today released updates to plug at least 110 security holes in its Windows operating systems and other products. The patches include four security fixes for Microsoft Exchange Server — the same systems that have been besieged by attacks on four separate (and zero-day) bugs in the email software over the past month. Redmond also patched a Windows flaw that is actively being exploited in the wild.

Nineteen of the vulnerabilities fixed this month earned Microsoft’s most-dire “Critical” label, meaning they could be used by malware or malcontents to seize remote control over vulnerable Windows systems without any help from users.

Microsoft released updates to fix four more flaws in Exchange Server versions 2013-2019 (CVE-2021-28480, CVE-2021-28481, CVE-2021-28482, CVE-2021-28483). Interestingly, all four were reported by the U.S. National Security Agency, although Microsoft says it also found two of the bugs internally. A Microsoft blog post published along with today’s patches urges Exchange Server users to make patching their systems a top priority.

Satnam Narang, staff research engineer at Tenable, said these vulnerabilities have been rated ‘Exploitation More Likely’ using Microsoft’s Exploitability Index.

“Two of the four vulnerabilities (CVE-2021-28480, CVE-2021-28481) are pre-authentication, meaning an attacker does not need to authenticate to the vulnerable Exchange server to exploit the flaw,” Narang said. “With the intense interest in Exchange Server since last month, it is crucial that organizations apply these Exchange Server patches immediately.”

Also patched today was a vulnerability in Windows (CVE-2021-28310) that’s being exploited in active attacks already. The flaw allows an attacker to elevate their privileges on a target system.

“This does mean that they will either need to log on to a system or trick a legitimate user into running the code on their behalf,” said Dustin Childs of Trend Micro. “Considering who is listed as discovering this bug, it is probably being used in malware. Bugs of this nature are typically combined with other bugs, such as browser bug of PDF exploit, to take over a system.”

In a technical writeup on what they’ve observed since finding and reporting attacks on CVE-2021-28310, researchers at Kaspersky Lab noted the exploit they saw was likely used together with other browser exploits to escape “sandbox” protections of the browser.

“Unfortunately, we weren’t able to capture a full chain, so we don’t know if the exploit is used with another browser zero-day, or coupled with known, patched vulnerabilities,” Kaspersky’s researchers wrote.

Allan Laska, senior security architect at Recorded Future, notes that there are several remote code execution vulnerabilities in Microsoft Office products released this month as well. CVE-2021-28454 and CVE-2021-28451 involve Excel, while CVE-2021-28453 is in Microsoft Word and CVE-2021-28449 is in Microsoft Office. All four vulnerabilities are labeled by Microsoft as “Important” (not quite as bad as “Critical”). These vulnerabilities impact all versions of their respective products, including Office 365.

Other Microsoft products that got security updates this month include Edge (Chromium-based), Azure and Azure DevOps Server, SharePoint Server, Hyper-V, Team Foundation Server, and Visual Studio.

Separately, Adobe has released security updates for Photoshop, Digital Editions, RoboHelp, and Bridge.

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.

Someone is selling account information for 21 million customers of ParkMobile, a mobile parking app that’s popular in North America. The stolen data includes customer email addresses, dates of birth, phone numbers, license plate numbers, hashed passwords and mailing addresses.

KrebsOnSecurity first heard about the breach from Gemini Advisory, a New York City based threat intelligence firm that keeps a close eye on the cybercrime forums. Gemini shared a new sales thread on a Russian-language crime forum that included my ParkMobile account information in the accompanying screenshot of the stolen data.

Included in the data were my email address and phone number, as well as license plate numbers for four different vehicles we have used over the past decade.

Asked about the sales thread, Atlanta-based ParkMobile said the company published a notification on Mar. 26 about “a cybersecurity incident linked to a vulnerability in a third-party software that we use.”

“In response, we immediately launched an investigation with the assistance of a leading cybersecurity firm to address the incident,” the notice reads. “Out of an abundance of caution, we have also notified the appropriate law enforcement authorities. The investigation is ongoing, and we are limited in the details we can provide at this time.”

The statement continues: “Our investigation indicates that no sensitive data or Payment Card Information, which we encrypt, was affected. Meanwhile, we have taken additional precautionary steps since learning of the incident, including eliminating the third-party vulnerability, maintaining our security, and continuing to monitor our systems.”

Asked for clarification on what the attackers did access, ParkMobile confirmed it included basic account information – license plate numbers, and if provided, email addresses and/or phone numbers, and vehicle nickname.

“In a small percentage of cases, there may be mailing addresses,” spokesman Jeff Perkins said.

ParkMobile doesn’t store user passwords, but rather it stores the output of a fairly robust one-way password hashing algorithm called bcrypt, which is far more resource-intensive and expensive to crack than common alternatives like MD5. The database stolen from ParkMobile and put up for sale includes each user’s bcrypt hash.

“You are correct that bcrypt hashed and salted passwords were obtained,” Perkins said when asked about the screenshot in the database sales thread.

“Note, we do not keep the salt values in our system,” he said. “Additionally, the compromised data does not include parking history, location history, or any other sensitive information. Note, we do not collect social security numbers or driver’s license numbers from our users.”

ParkMobile says it is finalizing an update to its support site confirming the conclusion of its investigation. But I wonder how many of its users were even aware of this security incident. The Mar. 26 security notice does not appear to be linked to other portions of the ParkMobile site, and it is absent from the company’s list of recent press releases.

It’s also curious that ParkMobile hasn’t asked or forced its users to change their passwords as a precautionary measure. I used the ParkMobile app to reset my password, but there was no messaging in the app that suggested this was a timely thing to do.

So if you’re a ParkMobile user, changing your account password might be a pro move. If it’s any consolation, whoever is selling this data is doing so for an insanely high starting price ($125,000) that is unlikely to be paid by any cybercriminal to a new user with no reputation on the forum.

More importantly, if you used your ParkMobile password at any other site tied to the same email address, it’s time to change those credentials as well (and stop re-using passwords).

The breach comes at a tricky time for ParkMobile. On March 9, the European parking group EasyPark announced its plans to acquire the company, which operates in more than 450 cities in North America.

Ne’er-do-wells leaked personal data — including phone numbers — for some 553 million Facebook users this week. Facebook says the data was collected before 2020 when it changed things to prevent such information from being scraped from profiles. To my mind, this just reinforces the need to remove mobile phone numbers from all of your online accounts wherever feasible. Meanwhile, if you’re a Facebook product user and want to learn if your data was leaked, there are easy ways to find out.

The HaveIBeenPwned project, which collects and analyzes hundreds of database dumps containing information about billions of leaked accounts, has incorporated the data into his service. Facebook users can enter the mobile number (in international format) associated with their account and see if those digits were exposed in the new data dump (HIBP doesn’t show you any data, just gives you a yes/no on whether your data shows up).

The phone number associated with my late Facebook account (which I deleted in Jan. 2020) was not in HaveIBeenPwned, but then again Facebook claims to have more than 2.7 billion active monthly users.

It appears much of this database has been kicking around the cybercrime underground in one form or another since last summer at least. According to a Jan. 14, 2021 Twitter post from Under the Breach’s Alon Gal, the 533 million Facebook accounts database was first put up for sale back in June 2020, offering Facebook profile data from 100 countries, including name, mobile number, gender, occupation, city, country, and marital status.

Under The Breach also said back in January that someone had created a Telegram bot allowing users to query the database for a low fee, and enabling people to find the phone numbers linked to a large number of Facebook accounts.

Many people may not consider their mobile phone number to be private information, but there is a world of misery that bad guys, stalkers and creeps can visit on your life just by knowing your mobile number. Sure they could call you and harass you that way, but more likely they will see how many of your other accounts — at major email providers and social networking sites like Facebook, Twitter, Instagram, e.g. — rely on that number for password resets.

From there, the target is primed for a SIM-swapping attack, where thieves trick or bribe employees at mobile phone stores into transferring ownership of the target’s phone number to a mobile device controlled by the attackers. From there, the bad guys can reset the password of any account to which that mobile number is tied, and of course intercept any one-time tokens sent to that number for the purposes of multi-factor authentication.

Or the attackers take advantage of some other privacy and security wrinkle in the way SMS text messages are handled. Last month, a security researcher showed how easy it was to abuse services aimed at helping celebrities manage their social media profiles to intercept SMS messages for any mobile user. That weakness has supposedly been patched for all the major wireless carriers now, but it really makes you question the ongoing sanity of relying on the Internet equivalent of postcards (SMS) to securely handle quite sensitive information.

In case readers want to get in touch for any reason, my email here is krebsonsecurity at gmail dot com, or krebsonsecurity at protonmail.com. I also respond at Krebswickr on the encrypted messaging platform Wickr.

Some of the top ransomware gangs are deploying a new pressure tactic to push more victim organizations into paying an extortion demand: Emailing the victim’s customers and partners directly, warning that their data will be leaked to the dark web unless they can convince the victim firm to pay up.

“Good day! If you received this letter, you are a customer, buyer, partner or employee of [victim],” the missive reads. “The company has been hacked, data has been stolen and will soon be released as the company refuses to protect its peoples’ data.”

“We inform you that information about you will be published on the darknet [link to dark web victim shaming page] if the company does not contact us,” the message concludes. “Call or write to this store and ask to protect your privacy!!!!”

The message above was sent to a customer of RaceTrac Petroleum, an Atlanta company that operates more than 650 retail gasoline convenience stores in 12 southeastern states. The person who shared that screenshot above isn’t a distributor or partner of RaceTrac, but they said they are a RaceTrac rewards member, so the company definitely has their email address and other information.

Several gigabytes of the company’s files — including employee tax and financial records — have been posted to the victim shaming site for the Clop ransomware gang.

In response to questions from KrebsOnSecurity, RaceTrac said it was recently impacted by a security incident affecting one of its third-party service providers, Accellion Inc.

For the past few months, attackers have been exploiting a a zero-day vulnerability in Accellion File Transfer Appliance (FTA) software, a flaw that has been seized upon by Clop to break into dozens of other major companies like oil giant Shell and security firm Qualys.

“By exploiting a previously undetected software vulnerability, unauthorized parties were able to access a subset of RaceTrac data stored in the Accellion File Transfer Service, including email addresses and first names of some of our RaceTrac Rewards Loyalty users,” the company wrote. “This incident was limited to the aforementioned Accellion services and did not impact RaceTrac’s corporate network. The systems used for processing guest credit, debit and RaceTrac Rewards transactions were not impacted.”

The same extortion pressure email has been going out to people associated with the University of California, which was one of several large U.S. universities that got hit with Clop ransomware recently. Most of those university ransomware incidents appeared to be tied to attacks on attacks on the same Accellion vulnerability, and the company has acknowledged roughly a third of its customers on that appliance got compromised as a result.

Clop is one of several ransom gangs that will demand two ransoms: One for a digital key needed to unlock computers and data from file encryption, and a second to avoid having stolen data published or sold online. That means even victims who opt not to pay to get their files and servers back still have to decide whether to pay the second ransom to protect the privacy of their customers.

As I noted in Why Paying to Delete Stolen Data is Bonkers, leaving aside the notion that victims might have any real expectation the attackers will actually destroy the stolen data, new research suggests a fair number of victims who do pay up may see some or all of the stolen data published anyway.

The email in the screenshot above differs slightly from those covered last week by Bleeping Computer, which was the first to spot the new victim notification wrinkle. Those emails say that the recipient is being contacted as they are a customer of the store, and their personal data, including phone numbers, email addresses, and credit card information, will soon be published if the store does not pay a ransom, writes Lawrence Abrams.

“Perhaps you bought something there and left your personal data. Such as phone, email, address, credit card information and social security number,” the Clop gang states in the email.

Fabian Wosar, chief technology officer at computer security firm Emsisoft, said the direct appeals to victim customers is a natural extension of other advertising efforts by the ransomware gangs, which recently included using hacked Facebook accounts to post victim shaming advertisements.

Wosar said Clop isn’t the only ransomware gang emailing victim customers.

“Clop likes to do it and I think REvil started as well,” Wosar said.

Earlier this month, Bleeping Computer reported that the REvil ransomware operation was planning on launching crippling distributed denial of service (DDoS) attacks against victims, or making VOIP calls to victims’ customers to apply further pressure.

“Sadly, regardless of whether a ransom is paid, consumers whose data has been stolen are still at risk as there is no way of knowing if ransomware gangs delete the data as they promise,” Abrams wrote.

For four days this past week, Internet-of-Things giant Ubiquiti failed to respond to requests for comment on a whistleblower’s allegations the company had massively downplayed a “catastrophic” two-month breach ending in January to save its stock price, and that Ubiquiti’s insinuation that a third-party was to blame was a fabrication. I was happy to add their eventual public response to the top of Tuesday’s story on the whistleblower’s claims, but their statement deserves a post of its own because it actually confirms and reinforces those claims.

Ubiquiti’s IoT gear includes things like WiFi routers, security cameras, and network video recorders. Their products have long been popular with security nerds and DIY types because they make it easy for users to build their own internal IoT networks without spending many thousands of dollars.

But some of that shine started to come off recently for Ubiquiti’s more security-conscious customers after the company began pushing everyone to use a unified authentication and access solution that makes it difficult to administer these devices without first authenticating to Ubiquiti’s cloud infrastructure.

All of a sudden, local-only networks were being connected to Ubiquiti’s cloud, giving rise to countless discussion threads on Ubiquiti’s user forums from customers upset over the potential for introducing new security risks.

And on Jan. 11, Ubiquiti gave weight to that angst: It told customers to reset their passwords and enable multifactor authentication, saying a breach involving a third-party cloud provider might have exposed user account data. Ubiquiti told customers they were “not currently aware of evidence of access to any databases that host user data, but we cannot be certain that user data has not been exposed.”

On Tuesday, KrebsOnSecurity reported that a source who participated in the response to the breach said Ubiquiti should have immediately invalidated all credentials because all of the company’s key administrator passwords had been compromised as well. The whistleblower also said Ubiquiti never kept any logs of who was accessing its databases.

The whistleblower, “Adam,” spoke on condition of anonymity for fear of reprisals from Ubiquiti. Adam said the place where those key administrator credentials were compromised — Ubiquiti’s presence on Amazon’s Web Services (AWS) cloud services — was in fact the “third party” blamed for the hack.

From Tuesday’s piece:

“In reality, Adam said, the attackers had gained administrative access to Ubiquiti’s servers at Amazon’s cloud service, which secures the underlying server hardware and software but requires the cloud tenant (client) to secure access to any data stored there.

“They were able to get cryptographic secrets for single sign-on cookies and remote access, full source code control contents, and signing keys exfiltration,” Adam said.

Adam says the attacker(s) had access to privileged credentials that were previously stored in the LastPass account of a Ubiquiti IT employee, and gained root administrator access to all Ubiquiti AWS accounts, including all S3 data buckets, all application logs, all databases, all user database credentials, and secrets required to forge single sign-on (SSO) cookies.

Such access could have allowed the intruders to remotely authenticate to countless Ubiquiti cloud-based devices around the world. According to its website, Ubiquiti has shipped more than 85 million devices that play a key role in networking infrastructure in over 200 countries and territories worldwide.

Ubiquiti finally responded on Mar. 31, in a post signed “Team UI” on the company’s community forum online.

“Nothing has changed with respect to our analysis of customer data and the security of our products since our notification on January 11. In response to this incident, we leveraged external incident response experts to conduct a thorough investigation to ensure the attacker was locked out of our systems.”

“These experts identified no evidence that customer information was accessed, or even targeted. The attacker, who unsuccessfully attempted to extort the company by threatening to release stolen source code and specific IT credentials, never claimed to have accessed any customer information. This, along with other evidence, is why we believe that customer data was not the target of, or otherwise accessed in connection with, the incident.”

Ubiquiti also hinted it had an idea of who was behind the attack, saying it has “well-developed evidence that the perpetrator is an individual with intricate knowledge of our cloud infrastructure. As we are cooperating with law enforcement in an ongoing investigation, we cannot comment further.”

Ubiquiti’s statement largely confirmed the reporting here by not disputing any of the facts raised in the piece. And while it may seem that Ubiquiti is quibbling over whether data was in fact stolen, Adam said Ubiquiti can say there is no evidence that customer information was accessed because Ubiquiti failed to keep logs of who was accessing its databases.

“Ubiquiti had negligent logging (no access logging on databases) so it was unable to prove or disprove what they accessed, but the attacker targeted the credentials to the databases, and created Linux instances with networking connectivity to said databases,” Adam wrote in a whistleblower letter to European privacy regulators last month. “Legal overrode the repeated requests to force rotation of all customer credentials, and to revert any device access permission changes within the relevant period.”

It appears investors noticed the incongruity as well. Ubiquiti’s share price hardly blinked at the January breach disclosure. On the contrary, from Jan. 13 to Tuesday’s story its stock had soared from $243 to $370. By the end of trading day Mar. 30, UI had slipped to $349. By close of trading on Thursday (markets were closed Friday) the stock had fallen to $289.