Login
Virtual private networking (VPN) companies market their services as a way to prevent anyone from snooping on your Internet usage. But new research suggests this is a dangerous assumption when connecting to a VPN via an untrusted network, because attackers on the same network could force a target’s traffic off of the protection provided by their VPN without triggering any alerts to the user.
Image: Shutterstock.
When a device initially tries to connect to a network, it broadcasts a message to the entire local network stating that it is requesting an Internet address. Normally, the only system on the network that notices this request and replies is the router responsible for managing the network to which the user is trying to connect.
The machine on a network responsible for fielding these requests is called a Dynamic Host Configuration Protocol (DHCP) server, which will issue time-based leases for IP addresses. The DHCP server also takes care of setting a specific local address — known as an Internet gateway — that all connecting systems will use as a primary route to the Web.
VPNs work by creating a virtual network interface that serves as an encrypted tunnel for communications. But researchers at Leviathan Security say they’ve discovered it’s possible to abuse an obscure feature built into the DHCP standard so that other users on the local network are forced to connect to a rogue DHCP server.
“Our technique is to run a DHCP server on the same network as a targeted VPN user and to also set our DHCP configuration to use itself as a gateway,” Leviathan researchers Lizzie Moratti and Dani Cronce wrote. “When the traffic hits our gateway, we use traffic forwarding rules on the DHCP server to pass traffic through to a legitimate gateway while we snoop on it.”
The feature being abused here is known as DHCP option 121, and it allows a DHCP server to set a route on the VPN user’s system that is more specific than those used by most VPNs. Abusing this option, Leviathan found, effectively gives an attacker on the local network the ability to set up routing rules that have a higher priority than the routes for the virtual network interface that the target’s VPN creates.
“Pushing a route also means that the network traffic will be sent over the same interface as the DHCP server instead of the virtual network interface,” the Leviathan researchers said. “This is intended functionality that isn’t clearly stated in the RFC [standard]. Therefore, for the routes we push, it is never encrypted by the VPN’s virtual interface but instead transmitted by the network interface that is talking to the DHCP server. As an attacker, we can select which IP addresses go over the tunnel and which addresses go over the network interface talking to our DHCP server.”
Leviathan found they could force VPNs on the local network that already had a connection to arbitrarily request a new one. In this well-documented tactic, known as a DHCP starvation attack, an attacker floods the DHCP server with requests that consume all available IP addresses that can be allocated. Once the network’s legitimate DHCP server is completely tied up, the attacker can then have their rogue DHCP server respond to all pending requests.
“This technique can also be used against an already established VPN connection once the VPN user’s host needs to renew a lease from our DHCP server,” the researchers wrote. “We can artificially create that scenario by setting a short lease time in the DHCP lease, so the user updates their routing table more frequently. In addition, the VPN control channel is still intact because it already uses the physical interface for its communication. In our testing, the VPN always continued to report as connected, and the kill switch was never engaged to drop our VPN connection.”
The researchers say their methods could be used by an attacker who compromises a DHCP server or wireless access point, or by a rogue network administrator who owns the infrastructure themselves and maliciously configures it. Alternatively, an attacker could set up an “evil twin” wireless hotspot that mimics the signal broadcast by a legitimate provider.
Bill Woodcock is executive director at Packet Clearing House, a nonprofit based in San Francisco. Woodcock said Option 121 has been included in the DHCP standard since 2002, which means the attack described by Leviathan has technically been possible for the last 22 years.
“They’re realizing now that this can be used to circumvent a VPN in a way that’s really problematic, and they’re right,” Woodcock said.
Woodcock said anyone who might be a target of spear phishing attacks should be very concerned about using VPNs on an untrusted network.
“Anyone who is in a position of authority or maybe even someone who is just a high net worth individual, those are all very reasonable targets of this attack,” he said. “If I were trying to do an attack against someone at a relatively high security company and I knew where they typically get their coffee or sandwich at twice a week, this is a very effective tool in that toolbox. I’d be a little surprised if it wasn’t already being exploited in that way, because again this isn’t rocket science. It’s just thinking a little outside the box.”
Successfully executing this attack on a network likely would not allow an attacker to see all of a target’s traffic or browsing activity. That’s because for the vast majority of the websites visited by the target, the content is encrypted (the site’s address begins with https://). However, an attacker would still be able to see the metadata — such as the source and destination addresses — of any traffic flowing by.
KrebsOnSecurity shared Leviathan’s research with John Kristoff, founder of dataplane.org and a PhD candidate in computer science at the University of Illinois Chicago. Kristoff said practically all user-edge network gear, including WiFi deployments, support some form of rogue DHCP server detection and mitigation, but that it’s unclear how widely deployed those protections are in real-world environments.
“However, and I think this is a key point to emphasize, an untrusted network is an untrusted network, which is why you’re usually employing the VPN in the first place,” Kristoff said. “If [the] local network is inherently hostile and has no qualms about operating a rogue DHCP server, then this is a sneaky technique that could be used to de-cloak some traffic – and if done carefully, I’m sure a user might never notice.”
According to Leviathan, there are several ways to minimize the threat from rogue DHCP servers on an unsecured network. One is using a device powered by the Android operating system, which apparently ignores DHCP option 121.
Relying on a temporary wireless hotspot controlled by a cellular device you own also effectively blocks this attack.
“They create a password-locked LAN with automatic network address translation,” the researchers wrote of cellular hot-spots. “Because this network is completely controlled by the cellular device and requires a password, an attacker should not have local network access.”
Leviathan’s Moratti said another mitigation is to run your VPN from inside of a virtual machine (VM) — like Parallels, VMware or VirtualBox. VPNs run inside of a VM are not vulnerable to this attack, Moratti said, provided they are not run in “bridged mode,” which causes the VM to replicate another node on the network.
In addition, a technology called “deep packet inspection” can be used to deny all in- and outbound traffic from the physical interface except for the DHCP and the VPN server. However, Leviathan says this approach opens up a potential “side channel” attack that could be used to determine the destination of traffic.
“This could be theoretically done by performing traffic analysis on the volume a target user sends when the attacker’s routes are installed compared to the baseline,” they wrote. “In addition, this selective denial-of-service is unique as it could be used to censor specific resources that an attacker doesn’t want a target user to connect to even while they are using the VPN.”
Moratti said Leviathan’s research shows that many VPN providers are currently making promises to their customers that their technology can’t keep.
“VPNs weren’t designed to keep you more secure on your local network, but to keep your traffic more secure on the Internet,” Moratti said. “When you start making assurances that your product protects people from seeing your traffic, there’s an assurance or promise that can’t be met.”
A copy of Leviathan’s research, along with code intended to allow others to duplicate their findings in a lab environment, is available here.
Image: Shutterstock.
A cybersecurity firm says it has intercepted a large, unique stolen data set containing the names, addresses, email addresses, phone numbers, Social Security Numbers and dates of birth on nearly 23 million Americans. The firm’s analysis of the data suggests it corresponds to current and former customers of AT&T. The telecommunications giant stopped short of saying the data wasn’t theirs, but it maintains the records do not appear to have come from its systems and may be tied to a previous data incident at another company.
Milwaukee-based cybersecurity consultancy Hold Security said it intercepted a 1.6 gigabyte compressed file on a popular dark web file-sharing site. The largest item in the archive is a 3.6 gigabyte file called “dbfull,” and it contains 28.5 million records, including 22.8 million unique email addresses and 23 million unique SSNs. There are no passwords in the database.
Hold Security founder Alex Holden said a number of patterns in the data suggest it relates to AT&T customers. For starters, email addresses ending in “att.net” accounted for 13.7 percent of all addresses in the database, with addresses from SBCGLobal.net and Bellsouth.net — both AT&T companies — making up another seven percent. In contrast, Gmail users made up more than 30 percent of the data set, with Yahoo addresses accounting for 24 percent. More than 10,000 entries in the database list “none@att.com” in the email field.
Hold Security found these email domains account for 87% of all domains in the data set. Nearly 21% belonged to AT&T customers.
Holden’s team also examined the number of email records that included an alias in the username portion of the email, and found 293 email addresses with plus addressing. Of those, 232 included an alias that indicated the customer had signed up at some AT&T property; 190 of the aliased email addresses were “+att@”; 42 were “+uverse@,” an oddly specific reference to an AT&T entity that included broadband Internet. In September 2016, AT&T rebranded U-verse as AT&T Internet.
According to its website, AT&T Internet is offered in 21 states, including Alabama, Arkansas, California, Florida, Georgia, Indiana, Kansas, Kentucky, Louisiana, Michigan, Missouri, Nevada, North Carolina, Ohio, Oklahoma, Tennessee, Texas and Wisconsin. Nearly all of the records in the database that contain a state designation corresponded to those 21 states; all other states made up just 1.64 percent of the records, Hold Security found.
Image: Hold Security.
The vast majority of records in this database belong to consumers, but almost 13,000 of the entries are for corporate entities. Holden said 387 of those corporate names started with “ATT,” with various entries like “ATT PVT XLOW” appearing 81 times. And most of the addresses for these entities are AT&T corporate offices.
How old is this data? One clue may be in the dates of birth exposed in this database. There are very few records in this file with dates of birth after 2000.
“Based on these statistics, we see that the last significant number of subscribers born in March of 2000,” Holden told KrebsOnSecurity, noting that AT&T requires new account holders to be 18 years of age or older. “Therefore, it makes sense that the dataset was likely created close to March of 2018.”
There was also this anomaly: Holden said one of his analysts is an AT&T customer with a 13-letter last name, and that her AT&T bill has always had the same unique misspelling of her surname (they added yet another letter). He said the analyst’s name is identically misspelled in this database.
KrebsOnSecurity shared the large data set with AT&T, as well as Hold Security’s analysis of it. AT&T ultimately declined to say whether all of the people in the database are or were at some point AT&T customers. The company said the data appears to be several years old, and that “it’s not immediately possible to determine the percentage that may be customers.”
“This information does not appear to have come from our systems,” AT&T said in a written statement. “It may be tied to a previous data incident at another company. It is unfortunate that data can continue to surface over several years on the dark web. However, customers often receive notices after such incidents, and advice for ID theft is consistent and can be found online.”
The company declined to elaborate on what they meant by “a previous data incident at another company.”
But it seems likely that this database is related to one that went up for sale on a hacker forum on August 19, 2021. That auction ran with the title “AT&T Database +70M (SSN/DOB),” and was offered by ShinyHunters, a well-known threat actor with a long history of compromising websites and developer repositories to steal credentials or API keys.
Image: BleepingComputer
ShinyHunters established the starting price for the auction at $200,000, but set the “flash” or “buy it now” price at $1 million. The auction also included a small sampling of the stolen information, but that sample is no longer available. The hacker forum where the ShinyHunters sales thread existed was seized by the FBI in April, and its alleged administrator arrested.
But cached copies of the auction, as recorded by cyber intelligence firm Intel 471, show ShinyHunters received bids of up to $230,000 for the entire database before they suspended the sale.
“This thread has been deleted several times,” ShinyHunters wrote in their auction discussion on Sept. 6, 2021. “Therefore, the auction is suspended. AT&T will be available on WHM as soon as they accept new vendors.”
The WHM initialism was a reference to the White House Market, a dark web marketplace that shut down in October 2021.
“In many cases, when a database is not sold, ShinyHunters will release it for free on hacker forums,” wrote BleepingComputer’s Lawrence Abrams, who broke the news of the auction last year and confronted AT&T about the hackers’ claims.
AT&T gave Abrams a similar statement, saying the data didn’t come from their systems.
“When asked whether the data may have come from a third-party partner, AT&T chose not to speculate,” Abrams wrote. “‘Given this information did not come from us, we can’t speculate on where it came from or whether it is valid,'” AT&T told BleepingComputer.
Asked to respond to AT&T’s denial, ShinyHunters told BleepingComputer at the time, “I don’t care if they don’t admit. I’m just selling.”
On June 1, 2022, a 21-year-old Frenchman was arrested in Morocco for allegedly being a member of ShinyHunters. Databreaches.net reports the defendant was arrested on an Interpol “Red Notice” at the request of a U.S. federal prosecutor from Washington state.
Databreaches.net suggests the warrant could be tied to a ShinyHunters theft in May 2020, when the group announced they had exfiltrated 500 GB of Microsoft’s source code from Microsoft’s private GitHub repositories.
“Researchers assess that Shiny Hunters gained access to roughly 1,200 private repositories around March 28, 2020, which have since been secured,” reads a May 2020 alert posted by the New Jersey Cybersecurity & Communications Integration Cell, a component within the New Jersey Office of Homeland Security and Preparedness.
“Though the breach was largely dismissed as insignificant, some images of the directory listing appear to contain source code for Azure, Office, and some Windows runtimes, and concerns have been raised regarding access to private API keys or passwords that may have been mistakenly included in some private repositories,” the alert continues. “Additionally, Shiny Hunters is flooding dark web marketplaces with breached databases.”
Last month, T-Mobile agreed to pay $350 million to settle a consolidated class action lawsuit over a breach in 2021 that affected 40 million current and former customers. The breach came to light on Aug. 16, 2021, when someone starting selling tens of millions of SSN/DOB records from T-Mobile on the same hacker forum where the ShinyHunters would post their auction for the claimed AT&T database just three days later.
T-Mobile has not disclosed many details about the “how” of last year’s breach, but it said the intruder(s) “leveraged their knowledge of technical systems, along with specialized tools and capabilities, to gain access to our testing environments and then used brute force attacks and other methods to make their way into other IT servers that included customer data.”
A sales thread tied to the stolen T-Mobile customer data.
The White House recently reissued a warning to American businesses in response to the unprecedented economic sanctions the U.S. has imposed on Russia for the Ukraine invasion, stating, “There is now evolving intelligence that Russia may be exploring options for potential cyberattacks.”
Along with this statement, the White House published a fact sheet outlining the new and ongoing steps the government is taking to protect its infrastructure and technologies, along with steps that private businesses can take to protect themselves from attacks as well.
Of course, any successful attack on government operations and the operations of private businesses could potentially affect households as well—such as in the case of data breaches where data or information is stolen from a system, often the personal data and information of individuals.
Word of potential attacks understandably leaves people feeling uncertain and may further leave them wondering if there’s anything they can do to protect themselves. With regards to data breaches and the cases of identity theft that typically follow, there are several steps people can take to keep safer online.
Let’s break down what a data breach looks like, how it can affect you, and what you can do in advance of a breach to protect yourself.
We’ve certainly seen data breaches make the news over the years, which are often (but not always) associated with malicious hackers or hacker organizations. A quick list of some of the largest and most impactful breaches we’ve seen in recent years:
Healthcare facilities have seen their data breached, along with the operations of popular restaurants. Small businesses find themselves in the crosshairs as well, with one report stating that 43% of data leaks target small businesses. Those may come by way of an attack on where those businesses store their records, a disgruntled employee, or by way of a compromised point-of-sale terminal in their store, office, or location.
What differs with the White House warning is who may end up being behind these potential attacks—a nation-state rather than what are financially motivated hackers or hacking groups. (Some research indicates that nearly 90% of breaches are about the money.) However, the result is the same. Your personal information winds up loose in the world and possibly in the hands of a bad actor.
The fact is that plenty of our information is out there on the internet, simply because we go about so much of our day online, whether that involves shopping, banking, getting results from our doctors, or simply hopping online to play a game once in a while.
Naturally, that means the data in any given breach will vary from service to service and platform to platform involved. Certainly, a gaming service will certainly have different information about you than your insurance company. Yet broadly speaking, there’s a broad range of information about you stored in various places, which could include:
As to what gets exposed and when you might find out about it, that can vary greatly as well. One industry research report found that 60% of breaches were discovered in just days from the initial attack while others could take months or even longer detect. Needless to say, the timeline can get rather stretched before word reaches you, which is a good reason to change your passwords regularly should any of them get swept up in a breach. (An outdated password does a hacker no good—more on that in a bit.)
The answer is plenty. In all, personal information like that listed above has a dollar value to it. In a way, your data and information are a kind of currency because they’re tied to everything from your bank accounts, investments, insurance payments—even tax returns and personal identification like driver’s licenses.
With this information in hand, a crook can commit several types of identity crimes—ranging from fraud to theft. In the case of fraud, that could include running up a bill on one of your credits cards or draining one of your bank accounts. In the case of theft, that could see crooks impersonate you so they can open new accounts or services in your name. Beyond that, they may attempt to claim your tax refund or potentially get an ID issued in your name as well.
Another possibility is that a hacker will simply sell that information on the dark marketplace, perhaps in large clumps or as individual pieces of information that go for a few dollars each. However it gets sold, these dark-market practices allow other fraudsters and thieves to take advantage of your identity for financial or another gain.
The succinct answer is to sign up for an identity protection service. It can monitor dozens of types of personal information and then alert you if any of them are possibly being misused, so you can address any issues right away before they become a potentially much bigger problem.
Further, pairing identity protection with online protection software can protect you even more. With an all-up view of your overall online security—how well you’re protecting yourself and your identity online—it can guide you through steps that can shore up your protection and make you safer still.
When a business, service, or organization falls victim to a breach, it doesn’t always mean that you’re automatically a victim too. Your information may not have been caught up in it. However, it’s best to act as if it was. With that, we strongly suggest you take these immediate steps.
Given the possibility that your password may be in the hands of a bad actor, change it right away. Strong, unique passwords offer one of your best defenses against hackers. Update them regularly as well. As mentioned above, this can protect you in the event a breach occurs and you don’t find out about it until well after it’s happened. You can spare yourself the upkeep that involves a password manager that can keep on top of it all for you. If your account offers two-factor authentication as part of the login process, make use of it as it adds another layer of security that makes hacking tougher.
If you spot unusual or unfamiliar charges or transactions in your account, bank, or debit card statements, follow up immediately. That could indicate improper use. In general, banks, credit card companies, and many businesses have countermeasures to deal with fraud, along with customer support teams that can help you file a claim if needed.
As outlined above, identity protection like ours can monitor a broad set of your personal information and provide you guidance for making it more secure, in addition to getting help from a professional recovery specialist.
For an even closer look at identity theft, we have two articles that can help guide the way if you think you’re a victim, each featuring a series of straightforward steps you can take to set matters right:
No matter how uncertain news of possible cyberattacks may any of us feel, you can take steps to set some of that uncertainty aside. An identity protection service is a strong first move against possible identity theft, as is pairing it with online protection software that keeps you safer online overall. Likewise, knowing the signs of possible identity theft and what you can do to address it right away offer further assurance still—like having the services of a professional recovery specialist to help.
In all, there’s no need to leave yourself wondering at the news from the White House. As an individual, you have it in your power to make yourself and your family safer than they are now.
The post White House Announces Possible Rise in Cyberattacks—What You Can Do to Stay Safe appeared first on McAfee Blog.
Most of us have fond summer memories of hanging out with friends in a secret clubhouse. However, this isn’t that. While the word clubhouse stirs up instant feelings of belonging to a group of friends, the digital Clubhouse app, we’re referencing is a meeting hub for users over 18. Currently, still in its beta phase, Clubhouse is by invitation only. This exclusivity is also what makes it somewhat irresistible for tweens and teens looking for a new place to meet with friends.
Clubhouse is an all-audio social network; kind of like a podcast meets a group phone call. Guests may drop in and even speak if they raise their hand are unmuted by the speaker. Speakers create “rooms” each with different topics and invite people to join in on that discussion.
The app found its wings as a fun place to connect during the pandemic. Mom groups, business roundtables, staff meetings, political groups, think tanks, and hobbyists flocked to connect on the app and still do. The topics are plentiful and there’s always a conversation happening that you can access with a click.
Currently there aren’t any parental controls or privacy settings on Clubhouse. While the app states that there’s a minimum age requirement of 18, there isn’t an actual age-verification system. As with so many other apps, anyone under 18 can simply get an invite, fake their age, and either drop in on any of the conversations going on or start their own room.
Mature content. Topics on Clubhouse cover a wide range of topics both mainstream and fringe. So, if an underage user fills out their profile information and interests, they will automatically get invitations to several daily discussions, which may or may not be age appropriate. They can also explore and join any kind of group.
Bullying. Clubhouse discussions are uncensored. Therefore, it’s possible that a heated discussion, biased comments, or bullying can take place.
Misinformation. If you walked through a crowded mall, you might overhear a dozen different accounts about a news event, a person, or a topic. The same holds true for Clubhouse where commentary is the currency. Therefore, misinformation is likely (as is common with any other app).
Accounts can’t be locked. Another privacy gap on Clubhouse is that accounts can’t be set to private and rooms/conversations will remain open by default unless the host makes it private, which means anyone can drop in.
The celebrity hook. Clubhouse has attracted celebrities and social media influencers to its halls who host discussions. This is a big draw for kids who want to hear real-life conversations and just get a bit closer to their favorite celebrity. Again, content can be unpredictable in these rooms and potentially risky for underage users.
Why age restrictions matter. More and more, kids who ignore age restrictions on apps are wandering into trouble. Consider talking to your child about why age restrictions exist, the consequences if they are ignored, and some alternative apps that might be safer.
Why privacy matters. While Clubhouse has grown prolifically in a short time, which has caused some concern over data privacy. According to reports, Clubhouse asks users to share their contacts and has been accused of being “overly aggressive with its connection recommendations.” Also, it’s unclear how the app collects and leverages user data. As outlined by McAfee’s Advanced Threat Research Team last month, the security of user information and communication within Clubhouse has vulnerabilities that could be exploited. For these reasons, consider discussing the data “exchange” we often make when we jump on an exciting new app, why data matters, and why it’s important to understand what’s being collected and to use any and all privacy settings. According to its privacy policy, Clubhouse also “temporarily record the audio in a room when it is live.”
Why content matters. With so many images and ideas coming across our screens every day, holding fast to our content standards can be a challenge for families. Talk to kids about why age-appropriate conversations, topics, and friend groups matter online and what happens when you try to speed up that process. Discuss how content filters and parental controls work and consider them for your family.
The good news about Clubhouse (when it comes to young users) is that along with its rapid growth, the creators are reportedly responding to consumer safety demands and daily increasing in-app safety features for reporting harassment and abuse.
To stay updated on all things McAfee and on top of the latest consumer and mobile security threats, follow @McAfee_Home on Twitter, subscribe to our email, listen to our podcast Hackable?, and ‘Like’ us on Facebook.
The post Is the Clubhouse App a Safe Place for Kids to Hangout? appeared first on McAfee Blogs.
FreshRSS 