CVE-2026-0100 Overview
CVE-2026-0100 is a heap buffer overflow vulnerability in the Android LoadedArsc::Load function within LoadedArsc.cpp. The flaw allows an out-of-bounds write when parsing Android resource (ARSC) data. An attacker with local access and low privileges can exploit this condition to escalate privileges without user interaction. Google addressed the issue in the Android Security Bulletin June 2026.
Critical Impact
Successful exploitation leads to local privilege escalation on affected Android devices, granting the attacker elevated execution context without requiring user interaction.
Affected Products
- Google Android 14.0
- Google Android 15.0
- Google Android 16.0 (including QPR2 Beta 1, Beta 2, and Beta 3)
Discovery Timeline
- 2026-06-01 - Google publishes Android Security Bulletin including patch for CVE-2026-0100
- 2026-06-01 - CVE-2026-0100 published to NVD
- 2026-06-03 - Last updated in NVD database
Technical Details for CVE-2026-0100
Vulnerability Analysis
The vulnerability resides in the Load method of the LoadedArsc class in LoadedArsc.cpp, a component of Android's resource loading framework. This code parses compiled Android resource tables (resources.arsc) shipped inside APK files. The flaw is a heap-based buffer overflow [CWE-122] producing an out-of-bounds write into heap memory.
An attacker who can deliver a malformed resource table to the affected parser triggers the overflow during normal load operations. The write occurs in privileged system context, allowing the attacker to corrupt adjacent heap structures. With careful heap shaping, this corruption can be steered toward local privilege escalation.
Exploitation requires local access and low-privilege execution on the device. No user interaction is required once a crafted resource file is processed. The result is full compromise of confidentiality, integrity, and availability within the affected process boundary.
Root Cause
The defect stems from insufficient bounds validation when reading offsets and lengths from attacker-controlled resource table headers. The LoadedArsc::Load parser trusts size fields embedded in the ARSC binary format. When these fields exceed the allocated heap buffer, the write proceeds past the buffer's end.
Attack Vector
A local attacker delivers a crafted APK or resource file that is parsed by an Android system component using LoadedArsc::Load. The malformed resources.arsc triggers the overflow during resource enumeration. The vulnerability mechanism is described in the Android Security Bulletin June 2026. No verified public exploit code is available.
Detection Methods for CVE-2026-0100
Indicators of Compromise
- Unexpected crashes or SIGSEGV signals in processes invoking LoadedArsc::Load, such as system_server or installd, during APK installation or resource parsing.
- Tombstone logs in /data/tombstones/ referencing heap corruption inside libandroidfw.so.
- Installation of APKs from untrusted sources immediately preceding abnormal system process behavior.
Detection Strategies
- Monitor Android device logs (logcat) for libc fatal signals and heap corruption errors tied to resource parsing.
- Inspect APK files at install time for malformed resources.arsc structures with inconsistent chunk sizes.
- Correlate package installation events with subsequent system process restarts on managed mobile fleets.
Monitoring Recommendations
- Forward Android tombstone and logcat data to a centralized logging platform for analysis.
- Track Android security patch levels across the device fleet and flag devices without the June 2026 patch.
- Alert on installation of sideloaded APKs from non-Play Store sources on enterprise-managed devices.
How to Mitigate CVE-2026-0100
Immediate Actions Required
- Apply the June 2026 Android security patch level (2026-06-01 or later) on all affected devices.
- Restrict installation of applications from unknown sources through enterprise mobile device management policy.
- Audit managed Android devices to confirm they receive vendor security updates on supported channels.
Patch Information
Google released the fix in the June 2026 Android Security Bulletin. Devices must be updated to a security patch level of 2026-06-01 or later. OEM rollout timing varies; consult the device manufacturer for availability. Reference: Android Security Bulletin June 2026.
Workarounds
- Block sideloading of APKs from untrusted sources using Android Enterprise restrictions until the patch is deployed.
- Limit the installation of third-party applications to vetted internal stores or Google Play Protect-verified apps.
- Isolate unpatched devices from access to sensitive corporate resources until the security update is applied.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
