Introduction
Attackers have leveraged a use after free flaw in Android Runtime to escape Chrome's sandbox and compromise the system_server process on Android devices. This vulnerability has been observed in real-world, targeted attacks and affects a broad range of Android versions, making patching a priority for both enterprises and individuals.
Android is the most widely deployed mobile operating system globally, with billions of active devices. Its security model relies on process isolation, sandboxing, and a managed runtime (ART) that executes Java and Kotlin code. The system_server process is a privileged component responsible for core system services. Compromising it can lead to full device control.
Technical Information
CVE-2025-48543 is a use after free vulnerability (CWE-416) in the Android Runtime (ART) component. ART is the managed runtime environment that executes Java and Kotlin applications. The vulnerability arises from improper memory management within ART, specifically the handling of object lifecycles. When an object is freed but still referenced elsewhere, a dangling pointer is created. Attackers can exploit this by manipulating the freed memory region before it is reused, allowing them to inject malicious data or code.
The key exploitation vector involves a malicious process (often originating from a compromised Chrome renderer) escaping its sandbox by targeting the ART use after free flaw. Once the attacker controls the freed memory, they can escalate privileges to execute code in the context of the highly privileged system_server process. This enables actions such as disabling security controls, accessing sensitive data, or installing persistent malware. Notably, exploitation does not require user interaction, increasing the risk of silent compromise.
The vulnerability is actively exploited in the wild, with Google's Threat Analysis Group observing targeted attacks that chain Chrome renderer exploits with this ART flaw for full device takeover. The root cause is a failure to ensure proper object reference management within ART, leading to exploitable dangling pointers.
No public code snippets or proof of concept exploit code have been released as of the September 2025 disclosure.
Patch Information
In the September 2025 Android Security Bulletin, Google addressed CVE-2025-48543 in the Android Runtime (ART) component. This vulnerability affects Android versions 13 through 16. The patch enhances security checks within ART to prevent unauthorized privilege escalation. The fix is distributed via Google Play system updates, ensuring that devices with Google Mobile Services (GMS) receive protection promptly, even outside regular over the air updates.
Reference patch sources:
- https://source.android.com/docs/security/bulletin/2025-09-01
- https://thecyberexpress.com/cve-2025-48543-and-cve-2025-38352/
Affected Systems and Versions
- Android 13 (all releases)
- Android 14 (all releases)
- Android 15 (all releases)
- Android 16 (all releases)
All configurations using the Android Runtime (ART) component are vulnerable if running one of the above versions and not yet updated to the September 2025 patch level (2025-09-01 or later).
Vendor Security History
Google has previously addressed similar privilege escalation and sandbox escape vulnerabilities in Android system components, including the kernel and media framework. The Android Security team typically releases coordinated monthly security bulletins and distributes patches via Google Play system updates for supported devices. However, ecosystem fragmentation can delay patch delivery for some device models. Google's Threat Analysis Group has a track record of identifying and disclosing actively exploited vulnerabilities, reflecting a mature security response process.