Android is the primary cell working system to introduce superior mobile safety mitigations for each shoppers and enterprises. Android 14 introduces assist for IT directors to disable 2G assist of their managed machine fleet. Android 14 additionally introduces a function 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 protected from community packet injection, tampering, or eavesdropping on consumer visitors. Android doesn’t depend on link-layer encryption to handle this menace mannequin. As a substitute, Android establishes that every one community visitors needs to be end-to-end encrypted (E2EE).

When a consumer connects to mobile networks for his or her communications (knowledge, voice, or SMS), because of the 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’t reliably know the legitimacy of the mobile base station earlier than trying to connect with it. Attackers exploit this in various 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 danger 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 danger

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 america, for instance, most main carriers have shut down 2G networks. Nonetheless, all current cell gadgets nonetheless have assist for 2G. Because of this, when accessible, any cell machine will hook up with a 2G community. This happens robotically when 2G is the one community accessible, 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 degree of safety as subsequent cell generations do. Most notably, 2G networks based mostly on the International System for Cellular 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 power to silently downgrade the connectivity of a tool from each 5G and 4G all the way down to 2G, is the most typical use of FBSs, IMSI catchers and Stingrays.

Stingrays are obscure but very highly effective surveillance and interception instruments which were leveraged in a number of eventualities, starting from doubtlessly sideloading Pegasus malware into journalist telephones to a refined phishing scheme that allegedly impacted tons of of hundreds of customers with a single FBS. This Stingray-based fraud assault, which possible downgraded machine’s connections to 2G to inject SMSishing payloads, has highlighted the dangers of 2G connectivity.

To handle this danger, Android 12 launched a new function that permits customers to disable 2G on the modem degree. Pixel 6 was the primary machine to undertake this function and it’s now supported by all Android gadgets that conform to Radio HAL 1.6+. This function 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 affect of this function for at-risk customers, and we acknowledged how important disabling 2G is also for our Android Enterprise clients.

Enterprises that use smartphones and tablets require sturdy safety to safeguard delicate knowledge and Mental Property. Android Enterprise gives sturdy administration controls for connectivity security capabilities, together with the power to disable WiFi, Bluetooth, and even knowledge signaling over USB. Beginning in Android 14, enterprise clients and authorities businesses managing gadgets utilizing Android Enterprise will be capable to limit a tool’s means to downgrade to 2G connectivity.

The 2G safety enterprise management in Android 14 allows our clients to configure cell connectivity in response to their danger 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 mandatory, at all times conserving the 2G radio off or making certain workers are protected when touring to particular high-risk areas.

These new capabilities are a part of the excellent set of 200+ administration controls that Android gives IT directors by means of Android Enterprise. Android Enterprise additionally gives complete audit logging with over 80 occasions together with these new administration controls. Audit logs are a important a part of any group’s safety and compliance technique. They supply an in depth document 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 explicit visitors varieties are strictly protected solely by the mobile hyperlink layer cipher, which is absolutely 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 experiences recognized utilization of null ciphers in industrial networks, which exposes consumer voice and SMS visitors (similar to One-Time Password) to trivial over the air interception. Furthermore, some industrial Stingrays present performance to trick gadgets into believing ciphering shouldn’t be 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 attainable to put emergency calls over an unciphered connection. This performance will enormously enhance communication privateness for gadgets that undertake the most recent radio {hardware} abstraction layer (HAL). We anticipate this new connectivity safety function to be accessible 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 staff is recurrently concerned within the growth and enchancment of mobile safety requirements. We actively take part in requirements our bodies similar to GSMA Fraud and Safety Group in addition to the third Technology Partnership Venture (3GPP), notably its safety and privateness group (SA3). Our long-term objective 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 id, belief and entry management strategies that may 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 inner Google groups as effectively, together with the Android Purple Workforce 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 by way of our Android Safety and Privateness Analysis grant (ASPIRE) a venture to develop a proof-of-concept to judge mobile connectivity hardening in smartphones. The educational staff offered the consequence of that venture within the final ACM Convention on Safety and Privateness in Wi-fi and Cellular Networks.

The safety journey continues

Person safety and privateness, which incorporates the security of all consumer communications, is a precedence on Android. With upcoming Android releases, we are going to proceed so as to add extra options to harden the platform in opposition to mobile safety threats.

We stay up for discussing the way forward for telco community safety with our ecosystem and business companions and standardization our bodies. We may also proceed to accomplice with tutorial establishments to resolve complicated issues in community safety. We see super alternatives to curb FBS threats, and we’re excited to work with the broader business to resolve them.

Particular because of our colleagues who had 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