CVE-2023-20917

What it actually does

Logic error in onTargetSelected of ResolverActivity.java permits an application to select and share an incorrect file instead of the intended target, bypassing intended authorization checks and enabling local privilege escalation.

Why it matters to the business

An attacker with an app already installed on an Android device can gain unauthorized access to sensitive files and elevate privileges, potentially leading to data theft or further compromise of the device without user awareness or additional permissions.

How an attack unfolds

An attacker develops or deploys a malicious application that triggers the flawed file selection logic in ResolverActivity during intent resolution, causing the system to expose or share files outside the expected scope and allowing the app to read or manipulate protected content.

How to fix it

Apply the latest Android security patches or upgrade to a fixed version of Android that resolves the ResolverActivity logic error; monitor vendor security bulletins for Android ID A-242605257 and enforce timely OS updates across managed devices.

How to confirm the fix worked

Verify that devices are running patched Android releases by checking build fingerprints against published security bulletins; test intent resolution behavior in ResolverActivity with crafted file-sharing scenarios to confirm correct target selection.

Typical attack path

1. Deploy a malicious application to the target Android device
2. Trigger file-sharing intent resolution via the vulnerable ResolverActivity
3. Exploit the logic error to select an unauthorized file target
4. Escalate privileges locally to access sensitive data or system resources

How to detect it

Examine device logs for unexpected file access patterns during intent resolution in ResolverActivity; review application behavior for anomalous sharing of files not matching user-selected targets.

What your security team should do

• Prioritize deployment of Android security updates to all managed devices
• Review and restrict app installation sources to reduce exposure to malicious applications
• Monitor for post-patch regressions in file-sharing functionality