The U.S. government is warning that βsmart locksβ securing entry to an estimated 50,000 dwellings nationwide contain hard-coded credentials that can be used to remotely open any of the locks. The lockβs maker Chirp Systems remains unresponsive, even though it was first notified about the critical weakness in March 2021. Meanwhile, Chirpβs parent company, RealPage, Inc., is being sued by multiple U.S. states for allegedly colluding with landlords to illegally raise rents.
On March 7, 2024, the U.S. Cybersecurity & Infrastructure Security Agency (CISA) warned about a remotely exploitable vulnerability with βlow attack complexityβ in Chirp Systems smart locks.
βChirp Access improperly stores credentials within its source code, potentially exposing sensitive information to unauthorized access,β CISAβs alert warned, assigning the bug a CVSS (badness) rating of 9.1 (out of a possible 10). βChirp Systems has not responded to requests to work with CISA to mitigate this vulnerability.β
Matt Brown, the researcher CISA credits with reporting the flaw, is a senior systems development engineer at Amazon Web Services. Brown said he discovered the weakness and reported it to Chirp in March 2021, after the company that manages his apartment building started using Chirp smart locks and told everyone to install Chirpβs app to get in and out of their apartments.
βI use Android, which has a pretty simple workflow for downloading and decompiling the APK apps,β Brown told KrebsOnSecurity. βGiven that I am pretty picky about what I trust on my devices, I downloaded Chirp and after decompiling, found that they were storing passwords and private key strings in a file.β
Using those hard-coded credentials, Brown found an attacker could then connect to an application programming interface (API) that Chirp uses which is managed by smart lock vendor August.com, and use that to enumerate and remotely lock or unlock any door in any building that uses the technology.
Update, April 18, 11:55 a.m. ET: August has provided a statement saying it does not believe August or Yale locks are vulnerable to the hack described by Brown.
βWe were recently made aware of a vulnerability disclosure regarding access control systems provided by Chirp, using August and Yale locks in multifamily housing,β the company said. βUpon learning of these reports, we immediately and thoroughly investigated these claims. Our investigation found no evidence that would substantiate the vulnerability claims in either our product or Chirpβs as it relates to our systems.β
Update, April 25, 2:45 p.m. ET: Based on feedback from Chirp, CISA has downgraded the severity of this flaw and revised their security advisory to say that the hard-coded credentials do not appear to expose the devices to remote locking or unlocking. CISA says the hardcoded credentials could be used by an attacker within the range of Bluetooth (~30 meters) βto change the configuration settings within the Bluetooth beacon, effectively removing Bluetooth visibility from the device. This does not affect the deviceβs ability to lock or unlock access points, and access points can still be operated remotely by unauthorized users via other means.β
Brown said when he complained to his leasing office, they sold him a small $50 key fob that uses Near-Field Communications (NFC) to toggle the lock when he brings the fob close to his front door. But he said the fob doesnβt eliminate the ability for anyone to remotely unlock his front door using the exposed credentials and the Chirp mobile app.
Also, the fobs pass the credentials to his front door over the air in plain text, meaning someone could clone the fob just by bumping against him with a smartphone app made to read and write NFC tags.
Neither August nor Chirp Systems responded to requests for comment. Itβs unclear exactly how many apartments and other residences are using the vulnerable Chirp locks, but multiple articles about the company from 2020 state that approximately 50,000 units use Chirp smart locks with Augustβs API.
Roughly a year before Brown reported the flaw to Chirp Systems, the company was bought by RealPage, a firm founded in 1998 as a developer of multifamily property management and data analytics software. In 2021, RealPage was acquired by the private equity giant Thoma Bravo.
Brown said the exposure he found in Chirpβs products is βan obvious flaw that is super easy to fix.β
βItβs just a matter of them being motivated to do it,β he said. βBut theyβre part of a private equity company now, so theyβre not answerable to anybody. Itβs too bad, because itβs not like residents of [the affected] properties have another choice. Itβs either agree to use the app or move.β
In October 2022, an investigation by ProPublica examined RealPageβs dominance in the rent-setting software market, and that it found βuses a mysterious algorithm to help landlords push the highest possible rents on tenants.β
βFor tenants, the system upends the practice of negotiating with apartment building staff,β ProPublica found. βRealPage discourages bargaining with renters and has even recommended that landlords in some cases accept a lower occupancy rate in order to raise rents and make more money. One of the algorithmβs developers told ProPublica that leasing agents had βtoo much empathyβ compared to computer generated pricing.β
Last year, the U.S. Department of Justice threw its weight behind a massive lawsuit filed by dozens of tenants who are accusing the $9 billion apartment software company of helping landlords collude to inflate rents.
In February 2024, attorneys general for Arizona and the District of Columbia sued RealPage, alleging RealPageβs software helped create a rental monopoly.
A cybercrook who has been setting up websites that mimic the self-destructing message service privnote.com accidentally exposed the breadth of their operations recently when they threatened to sue a software company. The disclosure revealed a profitable network of phishing sites that behave and look like the real Privnote, except that any messages containing cryptocurrency addresses will be automatically altered to include a different payment address controlled by the scammers.
The real Privnote, at privnote.com.
Launched in 2008, privnote.com employs technology that encrypts each message so that even Privnote itself cannot read its contents. And it doesnβt send or receive messages. Creating a message merely generates a link. When that link is clicked or visited, the service warns that the message will be gone forever after it is read.
Privnoteβs ease-of-use and popularity among cryptocurrency enthusiasts has made it a perennial target of phishers, who erect Privnote clones that function more or less as advertised but also quietly inject their own cryptocurrency payment addresses when a note is created that contains crypto wallets.
Last month, a new user on GitHub named fory66399 lodged a complaint on the βissuesβ page for MetaMask, a software cryptocurrency wallet used to interact with the Ethereum blockchain. Fory66399 insisted that their website β privnote[.]co β was being wrongly flagged by MetaMaskβs βeth-phishing-detectβ list as malicious.
βWe filed a lawsuit with a lawyer for dishonestly adding a site to the block list, damaging reputation, as well as ignoring the moderation department and ignoring answers!β fory66399 threatened. βProvide evidence or I will demand compensation!β
MetaMaskβs lead product manager Taylor Monahan replied by posting several screenshots of privnote[.]co showing the site did indeed swap out any cryptocurrency addresses.
After being told where they could send a copy of their lawsuit, Fory66399 appeared to become flustered, and proceeded to mention a number of other interesting domain names:
You sent me screenshots from some other site! Itβs red!!!!
The tornote.io website has a different color altogether
The privatenote,io website also has a different color! Whatβs wrong?????
A search at DomainTools.com for privatenote[.]io shows it has been registered to two names over as many years, including Andrey Sokol from Moscow and Alexandr Ermakov from Kiev. There is no indication these are the real names of the phishers, but the names are useful in pointing to other sites targeting Privnote since 2020.
DomainTools says other domains registered to Alexandr Ermakov include pirvnota[.]com, privatemessage[.]net, privatenote[.]io, and tornote[.]io.
A screenshot of the phishing domain privatemessage dot net.
The registration records for pirvnota[.]com at one point were updated from Andrey Sokol to βBPWβ as the registrant organization, and βTambov districtβ in the registrant state/province field. Searching DomainTools for domains that include both of these terms reveals pirwnote[.]com.
Other Privnote phishing domains that also phoned home to the same Internet address as pirwnote[.]com include privnode[.]com, privnate[.]com, and prevnΓ³te[.]com. Pirwnote[.]com is currently selling security cameras made by the Chinese manufacturer Hikvision, via an Internet address based in Hong Kong.
It appears someone has gone to great lengths to make tornote[.]io seem like a legitimate website. For example, this account at Medium has authored more than a dozen blog posts in the past year singing the praises of Tornote as a secure, self-destructing messaging service. However, testing shows tornote[.]io will also replace any cryptocurrency addresses in messages with their own payment address.
These malicious note sites attract visitors by gaming search engine results to make the phishing domains appear prominently in search results for βprivnote.β A search in Google for βprivnoteβ currently returns tornote[.]io as the fifth result. Like other phishing sites tied to this network, Tornote will use the same cryptocurrency addresses for roughly 5 days, and then rotate in new payment addresses.
Tornote changed the cryptocurrency address entered into a test note to this address controlled by the phishers.
Throughout 2023, Tornote was hosted with the Russian provider DDoS-Guard, at the Internet address 186.2.163[.]216. A review of the passive DNS records tied to this address shows that apart from subdomains dedicated to tornote[.]io, the main other domain at this address was hkleaks[.]ml.
In August 2019, a slew of websites and social media channels dubbed βHKLEAKSβ began doxing the identities and personal information of pro-democracy activists in Hong Kong. According to a report (PDF) from Citizen Lab, hkleaks[.]ml was the second domain that appeared as the perpetrators began to expand the list of those doxed.
HKleaks, as indexed by The Wayback Machine.
DomainTools shows there are more than 1,000 other domains whose registration records include the organization name βBPWβ and βTambov Districtβ as the location. Virtually all of those domains were registered through one of two registrars β Hong Kong-based Nicenic and Singapore-based WebCC β and almost all appear to be phishing or pill-spam related.
Among those is rustraitor[.]info, a website erected after Russia invaded Ukraine in early 2022 that doxed Russians perceived to have helped the Ukrainian cause.
An archive.org copy of Rustraitor.
In keeping with the overall theme, these phishing domains appear focused on stealing usernames and passwords to some of the cybercrime undergroundβs busiest shops, including Brianβs Club. What do all the phished sites have in common? They all accept payment via virtual currencies.
It appears MetaMaskβs Monahan made the correct decision in forcing these phishers to tip their hand: Among the websites at that DDoS-Guard address are multiple MetaMask phishing domains, including metarrnask[.]com, meternask[.]com, and rnetamask[.]com.
How profitable are these private note phishing sites? Reviewing the four malicious cryptocurrency payment addresses that the attackers swapped into notes passed through privnote[.]co (as pictured in Monahanβs screenshot above) shows that between March 15 and March 19, 2024, those address raked in and transferred out nearly $18,000 in cryptocurrencies. And thatβs just one of their phishing websites.
Thread hijacking attacks. They happen when someone you know has their email account compromised, and you are suddenly dropped into an existing conversation between the sender and someone else. These missives draw on the recipientβs natural curiosity about being copied on a private discussion, which is modified to include a malicious link or attachment. Hereβs the story of a thread hijacking attack in which a journalist was copied on a phishing email from the unwilling subject of a recent scoop.
In Sept. 2023, the Pennsylvania news outlet LancasterOnline.com published a story about Adam Kidan, a wealthy businessman with a criminal past who is a major donor to Republican causes and candidates, including Rep. Lloyd Smucker (R-Pa).
The LancasterOnline story about Adam Kidan.
Several months after that piece ran, the storyβs author Brett Sholtis received two emails from Kidan, both of which contained attachments. One of the messages appeared to be a lengthy conversation between Kidan and a colleague, with the subject line, βRe: Successfully sent data.β The second missive was a more brief email from Kidan with the subject, βAcknowledge New Work Order,β and a message that read simply, βPlease find the attached.β
Sholtis said he clicked the attachment in one of the messages, which then launched a web page that looked exactly like a Microsoft Office 365 login page. An analysis of the webpage reveals it would check any submitted credentials at the real Microsoft website, and return an error if the user entered bogus account information. A successful login would record the submitted credentials and forward the victim to the real Microsoft website.
But Sholtis said he didnβt enter his Outlook username and password. Instead, he forwarded the messages to LancasterOnelineβs IT team, which quickly flagged them as phishing attempts.
LancasterOnline Executive Editor Tom Murse said the two phishing messages from Mr. Kidan raised eyebrows in the newsroom because Kidan had threatened to sue the news outlet multiple times over Sholtisβs story.
βWe were just perplexed,β Murse said. βIt seemed to be a phishing attempt but we were confused why it would come from a prominent businessman weβve written about. Our initial response was confusion, but we didnβt know what else to do with it other than to send it to the FBI.β
The phishing lure attached to the thread hijacking email from Mr. Kidan.
In 2006, Kidan was sentenced to 70 months in federal prison after pleading guilty to defrauding lenders along with Jack Abramoff, the disgraced lobbyist whose corruption became a symbol of the excesses of Washington influence peddling. He was paroled in 2009, and in 2014 moved his family to a home in Lancaster County, Pa.
The FBI hasnβt responded to LancasterOnlineβs tip. Messages sent by KrebsOnSecurity to Kidanβs emails addresses were returned as blocked. Messages left with Mr. Kidanβs company, Empire Workforce Solutions, went unreturned.
No doubt the FBI saw the messages from Kidan for what they likely were: The result of Mr. Kidan having his Microsoft Outlook account compromised and used to send malicious email to people in his contacts list.
Thread hijacking attacks are hardly new, but that is mainly true because many Internet users still donβt know how to identify them. The email security firm Proofpoint says it has tracked north of 90 million malicious messages in the last five years that leverage this attack method.
One key reason thread hijacking is so successful is that these attacks generally do not include the tell that exposes most phishing scams: A fabricated sense of urgency. A majority of phishing threats warn of negative consequences should you fail to act quickly β such as an account suspension or an unauthorized high-dollar charge going through.
In contrast, thread hijacking campaigns tend to patiently prey on the natural curiosity of the recipient.
Ryan Kalember, chief strategy officer at Proofpoint, said probably the most ubiquitous examples of thread hijacking are βCEO fraudβ or βbusiness email compromiseβ scams, wherein employees are tricked by an email from a senior executive into wiring millions of dollars to fraudsters overseas.
But Kalember said these low-tech attacks can nevertheless be quite effective because they tend to catch people off-guard.
βIt works because you feel like youβre suddenly included in an important conversation,β Kalember said. βIt just registers a lot differently when people start reading, because you think youβre observing a private conversation between two different people.β
Some thread hijacking attacks actually involve multiple threat actors who are actively conversing while copying β but not addressing β the recipient.
βWe call these multi-persona phishing scams, and theyβre often paired with thread hijacking,β Kalember said. βItβs basically a way to build a little more affinity than just copying people on an email. And the longer the conversation goes on, the higher their success rate seems to be because some people start replying to the thread [and participating] psycho-socially.β
The best advice to sidestep phishing scams is to avoid clicking on links or attachments that arrive unbidden in emails, text messages and other mediums. If youβre unsure whether the message is legitimate, take a deep breath and visit the site or service in question manually β ideally, using a browser bookmark so as to avoid potential typosquatting sites.
In my last blog, I shared the progress weβre making toward building the Cisco Security Cloud, an open, integrated security platform capable of tackling the rigors of securing highly distributed, mβ¦ Read more on Cisco Blogs
Several Apple customers recently reported being targeted in elaborate phishing attacks that involve what appears to be a bug in Appleβs password reset feature. In this scenario, a targetβs Apple devices are forced to display dozens of system-level prompts that prevent the devices from being used until the recipient responds βAllowβ or βDonβt Allowβ to each prompt. Assuming the user manages not to fat-finger the wrong button on the umpteenth password reset request, the scammers will then call the victim while spoofing Apple support in the caller ID, saying the userβs account is under attack and that Apple support needs to βverifyβ a one-time code.
Some of the many notifications Patel says he received from Apple all at once.
Parth Patel is an entrepreneur who is trying to build a startup in the conversational AI space. On March 23, Patel documented on Twitter/X a recent phishing campaign targeting him that involved whatβs known as a βpush bombingβ or βMFA fatigueβ attack, wherein the phishers abuse a feature or weakness of a multi-factor authentication (MFA) system in a way that inundates the targetβs device(s) with alerts to approve a password change or login.
βAll of my devices started blowing up, my watch, laptop and phone,β Patel told KrebsOnSecurity. βIt was like this system notification from Apple to approve [a reset of the account password], but I couldnβt do anything else with my phone. I had to go through and decline like 100-plus notifications.β
Some people confronted with such a deluge may eventually click βAllowβ to the incessant password reset prompts β just so they can use their phone again. Others may inadvertently approve one of these prompts, which will also appear on a userβs Apple watch if they have one.
But the attackers in this campaign had an ace up their sleeves: Patel said after denying all of the password reset prompts from Apple, he received a call on his iPhone that said it was from Apple Support (the number displayed was 1-800-275-2273, Appleβs real customer support line).
βI pick up the phone and Iβm super suspicious,β Patel recalled. βSo I ask them if they can verify some information about me, and after hearing some aggressive typing on his end he gives me all this information about me and itβs totally accurate.β
All of it, that is, except his real name. Patel said when he asked the fake Apple support rep to validate the name they had on file for the Apple account, the caller gave a name that was not his but rather one that Patel has only seen in background reports about him that are for sale at a people-search website called PeopleDataLabs.
Patel said he has worked fairly hard to remove his information from multiple people-search websites, and he found PeopleDataLabs uniquely and consistently listed this inaccurate name as an alias on his consumer profile.
βFor some reason, PeopleDataLabs has three profiles that come up when you search for my info, and two of them are mine but one is an elementary school teacher from the midwest,β Patel said. βI asked them to verify my name and they said Anthony.β
Patel said the goal of the voice phishers is to trigger an Apple ID reset code to be sent to the userβs device, which is a text message that includes a one-time password. If the user supplies that one-time code, the attackers can then reset the password on the account and lock the user out. They can also then remotely wipe all of the userβs Apple devices.
Chris is a cryptocurrency hedge fund owner who asked that only his first name be used so as not to paint a bigger target on himself. Chris told KrebsOnSecurity he experienced a remarkably similar phishing attempt in late February.
βThe first alert I got I hit βDonβt Allowβ, but then right after that I got like 30 more notifications in a row,β Chris said. βI figured maybe I sat on my phone weird, or was accidentally pushing some button that was causing these, and so I just denied them all.β
Chris says the attackers persisted hitting his devices with the reset notifications for several days after that, and at one point he received a call on his iPhone that said it was from Apple support.
βI said I would call them back and hung up,β Chris said, demonstrating the proper response to such unbidden solicitations. βWhen I called back to the real Apple, they couldnβt say whether anyone had been in a support call with me just then. They just said Apple states very clearly that it will never initiate outbound calls to customers β unless the customer requests to be contacted.β
Massively freaking out that someone was trying to hijack his digital life, Chris said he changed his passwords and then went to an Apple store and bought a new iPhone. From there, he created a new Apple iCloud account using a brand new email address.
Chris said he then proceeded to get even more system alerts on his new iPhone and iCloud account β all the while still sitting at the local Apple Genius Bar.
Chris told KrebsOnSecurity his Genius Bar tech was mystified about the source of the alerts, but Chris said he suspects that whatever the phishers are abusing to rapidly generate these Apple system alerts requires knowing the phone number on file for the targetβs Apple account. After all, that was the only aspect of Chrisβs new iPhone and iCloud account that hadnβt changed.
βKenβ is a security industry veteran who spoke on condition of anonymity. Ken said he first began receiving these unsolicited system alerts on his Apple devices earlier this year, but that he has not received any phony Apple support calls as others have reported.
βThis recently happened to me in the middle of the night at 12:30 a.m.,β Ken said. βAnd even though I have my Apple watch set to remain quiet during the time Iβm usually sleeping at night, it woke me up with one of these alerts. Thank god I didnβt press βAllow,β which was the first option shown on my watch. I had to scroll watch the wheel to see and press the βDonβt Allowβ button.β
Ken shared this photo he took of an alert on his watch that woke him up at 12:30 a.m. Ken said he had to scroll on the watch face to see the βDonβt Allowβ button.
Ken didnβt know it when all this was happening (and itβs not at all obvious from the Apple prompts), but clicking βAllowβ would not have allowed the attackers to change Kenβs password. Rather, clicking βAllowβ displays a six digit PIN that must be entered on Kenβs device β allowing Ken to change his password. It appears that these rapid password reset prompts are being used to make a subsequent inbound phone call spoofing Apple more believable.
Ken said he contacted the real Apple support and was eventually escalated to a senior Apple engineer. The engineer assured Ken that turning on an Apple Recovery Key for his account would stop the notifications once and for all.
A recovery key is an optional security feature that Apple says βhelps improve the security of your Apple ID account.β It is a randomly generated 28-character code, and when you enable a recovery key it is supposed to disable Appleβs standard account recovery process. The thing is, enabling it is not a simple process, and if you ever lose that code in addition to all of your Apple devices you will be permanently locked out.
Ken said he enabled a recovery key for his account as instructed, but that it hasnβt stopped the unbidden system alerts from appearing on all of his devices every few days.
KrebsOnSecurity tested Kenβs experience, and can confirm that enabling a recovery key does nothing to stop a password reset prompt from being sent to associated Apple devices. Visiting Appleβs βforgot passwordβ page β https://iforgot.apple.com β asks for an email address and for the visitor to solve a CAPTCHA.
After that, the page will display the last two digits of the phone number tied to the Apple account. Filling in the missing digits and hitting submit on that form will send a system alert, whether or not the user has enabled an Apple Recovery Key.
The password reset page at iforgot.apple.com.
What sanely designed authentication system would send dozens of requests for a password change in the span of a few moments, when the first requests havenβt even been acted on by the user? Could this be the result of a bug in Appleβs systems?
Apple has not yet responded to requests for comment.
Throughout 2022, a criminal hacking group known as LAPSUS$ used MFA bombing to great effect in intrusions at Cisco, Microsoft and Uber. In response, Microsoft began enforcing βMFA number matching,β a feature that displays a series of numbers to a user attempting to log in with their credentials. These numbers must then be entered into the account ownerβs Microsoft authenticator app on their mobile device to verify they are logging into the account.
Kishan Bagaria is a hobbyist security researcher and engineer who founded the website texts.com (now owned by Automattic), and heβs convinced Apple has a problem on its end. In August 2019, Bagaria reported to Apple a bug that allowed an exploit he dubbed βAirDoSβ because it could be used to let an attacker infinitely spam all nearby iOS devices with a system-level prompt to share a file via AirDrop β a file-sharing capability built into Apple products.
Apple fixed that bug nearly four months later in December 2019, thanking Bagaria in the associated security bulletin. Bagaria said Appleβs fix was to add stricter rate limiting on AirDrop requests, and he suspects that someone has figured out a way to bypass Appleβs rate limit on how many of these password reset requests can be sent in a given timeframe.
βI think this could be a legit Apple rate limit bug that should be reported,β Bagaria said.
Apple seems requires a phone number to be on file for your account, but after youβve set up the account it doesnβt have to be a mobile phone number. KrebsOnSecurityβs testing shows Apple will accept a VOIP number (like Google Voice). So, changing your account phone number to a VOIP number that isnβt widely known would be one mitigation here.
One caveat with the VOIP number idea: Unless you include a real mobile number, Appleβs iMessage and Facetime applications will be disabled for that device. This might a bonus for those concerned about reducing the overall attack surface of their Apple devices, since zero-click zero-days in these applications have repeatedly been used by spyware purveyors.
Also, it appears Appleβs password reset system will accept and respect email aliases. Adding a β+β character after the username portion of your email address β followed by a notation specific to the site youβre signing up at β lets you create an infinite number of unique email addresses tied to the same account.
For instance, if I were signing up at example.com, I might give my email address as krebsonsecurity+example@gmail.com. Then, I simply go back to my inbox and create a corresponding folder called βExample,β along with a new filter that sends any email addressed to that alias to the Example folder. In this case, however, perhaps a less obvious alias than β+appleβ would be advisable.
Update, March 27, 5:06 p.m. ET:Β Added perspective on Kenβs experience. Also included a What Can You Do? section.
There has been an exponential increase in breaches within enterprises despite the carefully constructed and controlled perimeters that exist around applications and data. Once an attacker can access⦠Read more on Cisco Blogs