Why Your Wi-Fi Router Doubles as an Apple AirTag

Apple and the satellite-based broadband service Starlink each recently took steps to address new research into the potential security and privacy implications of how their services geo-locate devices. Researchers from the University of Maryland say they relied on publicly available data from Apple to track the location of billions of devices globally — including non-Apple devices like Starlink systems — and found they could use this data to monitor the destruction of Gaza, as well as the movements and in many cases identities of Russian and Ukrainian troops.

At issue is the way that Apple collects and publicly shares information about the precise location of all Wi-Fi access points seen by its devices. Apple collects this location data to give Apple devices a crowdsourced, low-power alternative to constantly requesting global positioning system (GPS) coordinates.

Both Apple and Google operate their own Wi-Fi-based Positioning Systems (WPS) that obtain certain hardware identifiers from all wireless access points that come within range of their mobile devices. Both record the Media Access Control (MAC) address that a Wi-FI access point uses, known as a Basic Service Set Identifier or BSSID.

Periodically, Apple and Google mobile devices will forward their locations — by querying GPS and/or by using cellular towers as landmarks — along with any nearby BSSIDs. This combination of data allows Apple and Google devices to figure out where they are within a few feet or meters, and it’s what allows your mobile phone to continue displaying your planned route even when the device can’t get a fix on GPS.

With Google’s WPS, a wireless device submits a list of nearby Wi-Fi access point BSSIDs and their signal strengths — via an application programming interface (API) request to Google — whose WPS responds with the device’s computed position. Google’s WPS requires at least two BSSIDs to calculate a device’s approximate position.

Apple’s WPS also accepts a list of nearby BSSIDs, but instead of computing the device’s location based off the set of observed access points and their received signal strengths and then reporting that result to the user, Apple’s API will return the geolocations of up to 400 hundred more BSSIDs that are nearby the one requested. It then uses approximately eight of those BSSIDs to work out the user’s location based on known landmarks.

In essence, Google’s WPS computes the user’s location and shares it with the device. Apple’s WPS gives its devices a large enough amount of data about the location of known access points in the area that the devices can do that estimation on their own.

That’s according to two researchers at the University of Maryland, who theorized they could use the verbosity of Apple’s API to map the movement of individual devices into and out of virtually any defined area of the world. The UMD pair said they spent a month early in their research continuously querying the API, asking it for the location of more than a billion BSSIDs generated at random.

They learned that while only about three million of those randomly generated BSSIDs were known to Apple’s Wi-Fi geolocation API, Apple also returned an additional 488 million BSSID locations already stored in its WPS from other lookups.

UMD Associate Professor David Levin and Ph.D student Erik Rye found they could mostly avoid requesting unallocated BSSIDs by consulting the list of BSSID ranges assigned to specific device manufacturers. That list is maintained by the Institute of Electrical and Electronics Engineers (IEEE), which is also sponsoring the privacy and security conference where Rye is slated to present the UMD research later today.

Plotting the locations returned by Apple’s WPS between November 2022 and November 2023, Levin and Rye saw they had a near global view of the locations tied to more than two billion Wi-Fi access points. The map showed geolocated access points in nearly every corner of the globe, apart from almost the entirety of China, vast stretches of desert wilderness in central Australia and Africa, and deep in the rainforests of South America.

The researchers said that by zeroing in on or “geofencing” other smaller regions indexed by Apple’s location API, they could monitor how Wi-Fi access points moved over time. Why might that be a big deal? They found that by geofencing active conflict zones in Ukraine, they were able to determine the location and movement of Starlink devices used by both Ukrainian and Russian forces.

The reason they were able to do that is that each Starlink terminal — the dish and associated hardware that allows a Starlink customer to receive Internet service from a constellation of orbiting Starlink satellites — includes its own Wi-Fi access point, whose location is going to be automatically indexed by any nearby Apple devices that have location services enabled.

The University of Maryland team geo-fenced various conflict zones in Ukraine, and identified at least 3,722 Starlink terminals geolocated in Ukraine.

“We find what appear to be personal devices being brought by military personnel into war zones, exposing pre-deployment sites and military positions,” the researchers wrote. “Our results also show individuals who have left Ukraine to a wide range of countries, validating public reports of where Ukrainian refugees have resettled.”

In an interview with KrebsOnSecurity, the UMD team said they found that in addition to exposing Russian troop pre-deployment sites, the location data made it easy to see where devices in contested regions originated from.

“This includes residential addresses throughout the world,” Levin said. “We even believe we can identify people who have joined the Ukraine Foreign Legion.”

Levin and Rye said they shared their findings with Starlink in March 2024, and that Starlink told them the company began shipping software updates in 2023 that force Starlink access points to randomize their BSSIDs.

Starlink’s parent SpaceX did not respond to requests for comment. But the researchers shared a graphic they said was created from their Starlink BSSID monitoring data, which shows that just in the past month there was a substantial drop in the number of Starlink devices that were geo-locatable using Apple’s API.

They also shared a written statement they received from Starlink, which acknowledged that Starlink User Terminal routers originally used a static BSSID/MAC:

“In early 2023 a software update was released that randomized the main router BSSID. Subsequent software releases have included randomization of the BSSID of WiFi repeaters associated with the main router. Software updates that include the repeater randomization functionality are currently being deployed fleet-wide on a region-by-region basis. We believe the data outlined in your paper is based on Starlink main routers and or repeaters that were queried prior to receiving these randomization updates.”

The researchers also focused their geofencing on the Israel-Hamas war in Gaza, and were able to track the migration and disappearance of devices throughout the Gaza Strip as Israeli forces cut power to the country and bombing campaigns knocked out key infrastructure.

“As time progressed, the number of Gazan BSSIDs that are geolocatable continued to decline,” they wrote. “By the end of the month, only 28% of the original BSSIDs were still found in the Apple WPS.”

In late March 2024, Apple quietly updated its website to note that anyone can opt out of having the location of their wireless access points collected and shared by Apple — by appending “_nomap” to the end of the Wi-Fi access point’s name (SSID). Adding “_nomap” to your Wi-Fi network name also blocks Google from indexing its location.

Asked about the changes, Apple said they have respected the “_nomap” flag on SSIDs for some time, but that this was only called out in a support article earlier this year.

Rye said Apple’s response addressed the most depressing aspect of their research: That there was previously no way for anyone to opt out of this data collection.

“You may not have Apple products, but if you have an access point and someone near you owns an Apple device, your BSSID will be in [Apple’s] database,” he said. “What’s important to note here is that every access point is being tracked, without opting in, whether they run an Apple device or not. Only after we disclosed this to Apple have they added the ability for people to opt out.”

The researchers said they hope Apple will consider additional safeguards, such as proactive ways to limit abuses of its location API.

“It’s a good first step,” Levin said of Apple’s privacy update in March. “But this data represents a really serious privacy vulnerability. I would hope Apple would put further restrictions on the use of its API, like rate-limiting these queries to keep people from accumulating massive amounts of data like we did.”

The UMD researchers said they omitted certain details from their study to protect the users they were able to track, noting that the methods they used could present risks for those fleeing abusive relationships or stalkers.

“We observe routers move between cities and countries, potentially representing their owner’s relocation or a business transaction between an old and new owner,” they wrote. “While there is not necessarily a 1-to-1 relationship between Wi-Fi routers and users, home routers typically only have several. If these users are vulnerable populations, such as those fleeing intimate partner violence or a stalker, their router simply being online can disclose their new location.”

The researchers said Wi-Fi access points that can be created using a mobile device’s built-in cellular modem do not create a location privacy risk for their users because mobile phone hotspots will choose a random BSSID when activated.

“Modern Android and iOS devices will choose a random BSSID when you go into hotspot mode,” he said. “Hotspots are already implementing the strongest recommendations for privacy protections. It’s other types of devices that don’t do that.”

For example, they discovered that certain commonly used travel routers compound the potential privacy risks.

“Because travel routers are frequently used on campers or boats, we see a significant number of them move between campgrounds, RV parks, and marinas,” the UMD duo wrote. “They are used by vacationers who move between residential dwellings and hotels. We have evidence of their use by military members as they deploy from their homes and bases to war zones.”

A copy of the UMD research is available here (PDF).

Update, May 22, 4:54 p.m. ET: Added response from Apple.

U.S. Charges Russian Man as Boss of LockBit Ransomware Group

The United States joined the United Kingdom and Australia today in sanctioning 31-year-old Russian national Dmitry Yuryevich Khoroshev as the alleged leader of the infamous ransomware group LockBit. The U.S. Department of Justice also indicted Khoroshev and charged him with using Lockbit to attack more than 2,000 victims and extort at least $100 million in ransomware payments.

Khoroshev (Дмитрий Юрьевич Хорошев), a resident of Voronezh, Russia, was charged in a 26-count indictment by a grand jury in New Jersey.

“Dmitry Khoroshev conceived, developed, and administered Lockbit, the most prolific ransomware variant and group in the world, enabling himself and his affiliates to wreak havoc and cause billions of dollars in damage to thousands of victims around the globe,” U.S. Attorney Philip R. Sellinger said in a statement released by the Justice Department.

The indictment alleges Khoroshev acted as the LockBit ransomware group’s developer and administrator from its inception in September 2019 through May 2024, and that he typically received a 20 percent share of each ransom payment extorted from LockBit victims.

The government says LockBit victims included individuals, small businesses, multinational corporations, hospitals, schools, nonprofit organizations, critical infrastructure, and government and law-enforcement agencies.

“Khoroshev and his co-conspirators extracted at least $500 million in ransom payments from their victims and caused billions of dollars in broader losses, such as lost revenue, incident response, and recovery,” the DOJ said. “The LockBit ransomware group attacked more than 2,500 victims in at least 120 countries, including 1,800 victims in the United States.”

The unmasking of LockBitSupp comes nearly three months after U.S. and U.K. authorities seized the darknet websites run by LockBit, retrofitting it with press releases about the law enforcement action and free tools to help LockBit victims decrypt infected systems.

One of the blog captions that authorities left on the seized site was a teaser page that read, “Who is LockbitSupp?,” which promised to reveal the true identity of the ransomware group leader. That item featured a countdown clock until the big reveal, but when the site’s timer expired no such details were offered.

Following the FBI’s raid, LockBitSupp took to Russian cybercrime forums to assure his partners and affiliates that the ransomware operation was still fully operational. LockBitSupp also raised another set of darknet websites that soon promised to release data stolen from a number of LockBit victims ransomed prior to the FBI raid.

One of the victims LockBitSupp continued extorting was Fulton County, Ga. Following the FBI raid, LockbitSupp vowed to release sensitive documents stolen from the county court system unless paid a ransom demand before LockBit’s countdown timer expired. But when Fulton County officials refused to pay and the timer expired, no stolen records were ever published. Experts said it was likely the FBI had in fact seized all of LockBit’s stolen data.

LockBitSupp also bragged that their real identity would never be revealed, and at one point offered to pay $10 million to anyone who could discover their real name.

KrebsOnSecurity has been in intermittent contact with LockBitSupp for several months over the course of reporting on different LockBit victims. Reached at the same ToX instant messenger identity that the ransomware group leader has promoted on Russian cybercrime forums, LockBitSupp claimed the authorities named the wrong guy.

“It’s not me,” LockBitSupp replied in Russian. “I don’t understand how the FBI was able to connect me with this poor guy. Where is the logical chain that it is me? Don’t you feel sorry for a random innocent person?”

LockBitSupp, who now has a $10 million bounty for his arrest from the U.S. Department of State, has been known to be flexible with the truth. The Lockbit group routinely practiced “double extortion” against its victims — requiring one ransom payment for a key to unlock hijacked systems, and a separate payment in exchange for a promise to delete data stolen from its victims.

But Justice Department officials say LockBit never deleted its victim data, regardless of whether those organizations paid a ransom to keep the information from being published on LockBit’s victim shaming website.

Khoroshev is the sixth person officially indicted as active members of LockBit. The government says Russian national Artur Sungatov used LockBit ransomware against victims in manufacturing, logistics, insurance and other companies throughout the United States.

Ivan Gennadievich Kondratyev, a.k.a. “Bassterlord,” allegedly deployed LockBit against targets in the United States, Singapore, Taiwan, and Lebanon. Kondratyev is also charged (PDF) with three criminal counts arising from his alleged use of the Sodinokibi (aka “REvil“) ransomware variant to encrypt data, exfiltrate victim information, and extort a ransom payment from a corporate victim based in Alameda County, California.

In May 2023, U.S. authorities unsealed indictments against two alleged LockBit affiliates, Mikhail “Wazawaka” Matveev and Mikhail Vasiliev. In January 2022, KrebsOnSecurity published Who is the Network Access Broker ‘Wazawaka,’ which followed clues from Wazawaka’s many pseudonyms and contact details on the Russian-language cybercrime forums back to a 31-year-old Mikhail Matveev from Abaza, RU.

Matveev remains at large, presumably still in Russia. Meanwhile, the U.S. Department of State has a standing $10 million reward offer for information leading to Matveev’s arrest.

Vasiliev, 35, of Bradford, Ontario, Canada, is in custody in Canada awaiting extradition to the United States (the complaint against Vasiliev is at this PDF).

In June 2023, Russian national Ruslan Magomedovich Astamirov was charged in New Jersey for his participation in the LockBit conspiracy, including the deployment of LockBit against victims in Florida, Japan, France, and Kenya. Astamirov is currently in custody in the United States awaiting trial.

The Justice Department is urging victims targeted by LockBit to contact the FBI at https://lockbitvictims.ic3.gov/ to file an official complaint, and to determine whether affected systems can be successfully decrypted.