Android is the primary cell working system to introduce superior mobile safety mitigations for each customers and enterprises. Android 14 introduces assist for IT directors to disable 2G assist of their managed machine fleet. Android 14 additionally introduces a characteristic that disables assist for null-ciphered mobile connectivity.
Hardening community safety on Android
The Android Safety Mannequin assumes that every one networks are hostile to maintain customers secure from community packet injection, tampering, or eavesdropping on consumer visitors. Android doesn’t depend on link-layer encryption to handle this risk mannequin. As an alternative, Android establishes that every one community visitors ought to be end-to-end encrypted (E2EE).
When a consumer connects to mobile networks for his or her communications (knowledge, voice, or SMS), as a result of distinctive nature of mobile telephony, the hyperlink layer presents distinctive safety and privateness challenges. False Base Stations (FBS) and Stingrays exploit weaknesses in mobile telephony requirements to trigger hurt to customers. Moreover, a smartphone can not reliably know the legitimacy of the mobile base station earlier than making an attempt to connect with it. Attackers exploit this in a lot of methods, starting from visitors interception and malware sideloading, to stylish dragnet surveillance.
Recognizing the far reaching implications of those assault vectors, particularly for at-risk customers, Android has prioritized hardening mobile telephony. We’re tackling well-known insecurities such because the threat offered by 2G networks, the chance offered by null ciphers, different false base station (FBS) threats, and baseband hardening with our ecosystem companions.
2G and a historical past of inherent safety threat
The cell ecosystem is quickly adopting 5G, the most recent wi-fi normal for cell, and lots of carriers have began to show down 2G service. In the USA, for instance, most main carriers have shut down 2G networks. Nevertheless, all present cell gadgets nonetheless have assist for 2G. In consequence, when out there, any cell machine will connect with a 2G community. This happens robotically when 2G is the one community out there, however this may also be remotely triggered in a malicious assault, silently inducing gadgets to downgrade to 2G-only connectivity and thus, ignoring any non-2G community. This conduct occurs no matter whether or not native operators have already sundown their 2G infrastructure.
2G networks, first applied in 1991, don’t present the identical stage of safety as subsequent cell generations do. Most notably, 2G networks based mostly on the International System for Cell Communications (GSM) normal lack mutual authentication, which allows trivial Particular person-in-the-Center assaults. Furthermore, since 2010, safety researchers have demonstrated trivial over-the-air interception and decryption of 2G visitors.
The out of date safety of 2G networks, mixed with the flexibility to silently downgrade the connectivity of a tool from each 5G and 4G all the way down to 2G, is the commonest use of FBSs, IMSI catchers and Stingrays.
Stingrays are obscure but very highly effective surveillance and interception instruments which have been leveraged in a number of eventualities, starting from doubtlessly sideloading Pegasus malware into journalist telephones to a refined phishing scheme that allegedly impacted a whole lot of hundreds of customers with a single FBS. This Stingray-based fraud assault, which doubtless downgraded machine’s connections to 2G to inject SMSishing payloads, has highlighted the dangers of 2G connectivity.
To handle this threat, Android 12 launched a new characteristic that allows customers to disable 2G on the modem stage. Pixel 6 was the primary machine to undertake this characteristic and it’s now supported by all Android gadgets that conform to Radio HAL 1.6+. This characteristic was fastidiously designed to make sure that customers should not impacted when making emergency calls.
Mitigating 2G safety dangers for enterprises
The business acknowledged the numerous safety and privateness advantages and influence of this characteristic for at-risk customers, and we acknowledged how vital disabling 2G is also for our Android Enterprise prospects.
Enterprises that use smartphones and tablets require robust safety to safeguard delicate knowledge and Mental Property. Android Enterprise offers strong administration controls for connectivity security capabilities, together with the flexibility to disable WiFi, Bluetooth, and even knowledge signaling over USB. Beginning in Android 14, enterprise prospects and authorities companies managing gadgets utilizing Android Enterprise will have the ability to limit a tool’s skill to downgrade to 2G connectivity.
The 2G safety enterprise management in Android 14 allows our prospects to configure cell connectivity in response to their threat mannequin, permitting them to guard their managed gadgets from 2G visitors interception, Particular person-in-the-Center assaults, and different 2G-based threats. IT directors can configure this safety as essential, at all times preserving the 2G radio off or guaranteeing workers are protected when touring to particular high-risk places.
These new capabilities are a part of the excellent set of 200+ administration controls that Android offers IT directors by way of Android Enterprise. Android Enterprise additionally offers complete audit logging with over 80 occasions together with these new administration controls. Audit logs are a vital a part of any group’s safety and compliance technique. They supply an in depth report of all exercise on a system, which can be utilized to trace down unauthorized entry, determine safety breaches, and troubleshoot system issues.
Additionally in Android 14
The upcoming Android launch additionally tackles the chance of mobile null ciphers. Though all IP-based consumer visitors is protected and E2EE by the Android platform, mobile networks expose circuit-switched voice and SMS visitors. These two specific visitors varieties are strictly protected solely by the mobile hyperlink layer cipher, which is totally managed by the community with out transparency to the consumer. In different phrases, the community decides whether or not visitors is encrypted and the consumer has no visibility into whether or not it’s being encrypted.
Current reviews recognized utilization of null ciphers in industrial networks, which exposes consumer voice and SMS visitors (akin to One-Time Password) to trivial over the air interception. Furthermore, some industrial Stingrays present performance to trick gadgets into believing ciphering isn’t supported by the community, thus downgrading the connection to a null cipher and enabling visitors interception.
Android 14 introduces a consumer choice to disable assist, on the modem-level, for null-ciphered connections. Equally to 2G controls, it’s nonetheless doable to position emergency calls over an unciphered connection. This performance will drastically enhance communication privateness for gadgets that undertake the most recent radio {hardware} abstraction layer (HAL). We count on this new connectivity safety characteristic to be out there in additional gadgets over the subsequent few years as it’s adopted by Android OEMs.
Persevering with to accomplice to boost the business bar for mobile safety
Alongside our Android-specific work, the group is recurrently concerned within the improvement and enchancment of mobile safety requirements. We actively take part in requirements our bodies akin to GSMA Fraud and Safety Group in addition to the third Era Partnership Undertaking (3GPP), notably its safety and privateness group (SA3). Our long-term aim is to render FBS threats out of date.
Specifically, Android safety is main a brand new initiative inside GSMA’s Fraud and Safety Group (FASG) to discover the feasibility of contemporary identification, belief and entry management strategies that will allow radically hardening the safety of telco networks.
Our efforts to harden mobile connectivity undertake Android’s defense-in-depth technique. We recurrently accomplice with different inside Google groups as effectively, together with the Android Purple Group and our Vulnerability Rewards Program.
Furthermore, in alignment with Android’s openness in safety, we actively accomplice with prime tutorial teams in mobile safety analysis. For instance, in 2022 we funded through our Android Safety and Privateness Analysis grant (ASPIRE) a mission to develop a proof-of-concept to guage mobile connectivity hardening in smartphones. The educational group offered the consequence of that mission within the final ACM Convention on Safety and Privateness in Wi-fi and Cell Networks.
The safety journey continues
Consumer safety and privateness, which incorporates the security of all consumer communications, is a precedence on Android. With upcoming Android releases, we’ll proceed so as to add extra options to harden the platform in opposition to mobile safety threats.
We look ahead to discussing the way forward for telco community safety with our ecosystem and business companions and standardization our bodies. We can even proceed to accomplice with tutorial establishments to resolve complicated issues in community safety. We see great alternatives to curb FBS threats, and we’re excited to work with the broader business to resolve them.
Particular due to our colleagues who have been instrumental in supporting our mobile community safety efforts: Nataliya Stanetsky, Robert Greenwalt, Jayachandran C, Gil Cukierman, Dominik Maier, Alex Ross, Il-Sung Lee, Kevin Deus, Farzan Karimi, Xuan Xing, Wes Johnson, Thiébaud Weksteen, Pauline Anthonysamy, Liz Louis, Alex Johnston, Kholoud Mohamed, Pavel Grafov
