Google is tightening restrictions on one of mobile malware's most persistent entry points. With Android 17, the company is limiting access to its AccessibilityService API to verified Accessibility Tools only, a change that takes effect the moment a user switches on Advanced Protection.
The move, announced Thursday, targets a problem that has haunted Android security for years. The AccessibilityService API was built to help people with disabilities use their smartphones. Screen readers, voice control apps, and motor-assistance tools all rely on it. But the privileges it carries are significant. Apps that tap into the API can run in the background, observe what appears on screen, intercept UI events, and take actions inside other applications on a user's behalf. That set of capabilities made it a target for malware developers almost immediately after it was introduced.
Google stated in its announcement that the new version automatically restricts AccessibilityService access to verified Accessibility Tool applications, closing off a major attack avenue while keeping genuine assistive technology functional.
A Clichéd Attack Path
Malware families have been weaponizing Android's accessibility services since at least 2017. The list of known offenders runs long: Vultur, SharkBot, Xenomorph, BianLian, Anatsa (also tracked as TeaBot), and more recently BTMOB RAT, a remote access trojan documented attacking banking customers across Brazil, Argentina, Spain, Portugal, and Mexico through 2025 and 2026. According to Kaspersky data, trojans accounted for 40 percent of Android malware infections in Q1 2025, with nearly 12 percent of malicious apps falling into the banking trojan category that specifically abused the Accessibility API, totaling around 154,000 apps.
The attack chain is well understood. A malicious app, typically distributed through sideloaded APKs or disguised as something routine, tricks a user into granting accessibility permissions. The Anatsa trojan, for instance, slipped onto Google Play as a PDF viewer update as recently as July 2025. Once the permission is granted, the malware operates without root access. It can monitor keystrokes, layer fake login pages on top of legitimate banking apps, approve system dialogs silently, and initiate fraudulent fund transfers from financial applications without the user noticing anything unusual on screen. Google noted in its announcement that this access also allows malware to block its own uninstallation, locking users out of any easy remedy.
What Changes in Android 17
The new restriction applies specifically when Advanced Protection is active, a device-level security mode introduced with Android 16 that consolidates multiple hardening features under a single toggle. When a user enables it, the system now automatically enforces that only verified, legitimate accessibility apps can request AccessibilityService access. Everything else is denied.
This is part of a gradual tightening that has been underway for several years. Android 13 made it significantly harder for sideloaded apps to acquire accessibility permissions. In-call protections, rolled out more recently, prevent users from granting those permissions during a phone call, cutting off a common social engineering scenario. Google also introduced the `accessibilityDataSensitive` flag to let developers mark UI elements as off-limits to third-party accessibility readers.
The Rest of Android 17's Security Updates
The accessibility change is one piece of a wider hardening effort in Android 17. Intrusion Logging, developed in collaboration with Amnesty International's Security Lab and other civil society organizations, creates a persistent, privacy-preserving forensic record of sensitive system events. Amnesty's team simultaneously updated AndroidQF and its Mobile Verification Toolkit to process the new log format, making it immediately useful for researchers investigating suspected spyware infections.
USB Protection blocks new data connections over a USB port while the device is locked, preventing physical access attacks where an attacker might attempt to extract data or push commands through a connected cable. Google has also included an option to disable WebGPU, a graphics API that has surfaced in sophisticated browser-based exploit chains. Failed Authentication Lock responds to repeated incorrect login attempts by locking the device entirely, making brute-force attempts against a stolen or seized phone substantially harder.
A fifth addition, View Supporting Apps, gives users a clear window into which installed applications have checked whether Advanced Protection is active on the device.
For developers, Google confirmed that applications can receive a notification when a user enables Advanced Protection, allowing them to switch on their own high-security features automatically for that audience.
Existing Advanced Protection users will receive a notification when the new capabilities land on their device. Intrusion Logging is not switched on by default and must be enabled manually from the Advanced Protection settings page.