CVE-2024-20853 in ThemeStore
Summary
by MITRE • 04/02/2024
Improper verification of intent by broadcast receiver vulnerability in ThemeStore prior to 5.3.05.2 allows local attackers to write arbitrary files to sandbox of ThemeStore.
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Analysis
by VulDB Data Team • 03/12/2025
This vulnerability represents a critical security flaw in the ThemeStore application where the broadcast receiver fails to properly verify user intent before executing file operations. The issue stems from insufficient validation of incoming broadcast intents, allowing malicious local applications to craft specially crafted broadcasts that appear to originate from legitimate sources within the system. This improper verification mechanism creates a pathway for privilege escalation and arbitrary code execution within the application's sandbox environment.
The technical implementation of this vulnerability resides in the application's broadcast receiver component which handles incoming intents without adequate authentication or authorization checks. When a broadcast intent is received, the system should validate that the sender has proper permissions and that the intent contains valid parameters before proceeding with file operations. However, in versions prior to 5.3.05.2, the receiver accepts all incoming broadcasts without verifying the sender's identity or intent, creating a significant attack surface. This flaw aligns with CWE-284 which addresses improper access control mechanisms and specifically relates to inadequate verification of intent in inter-process communication.
The operational impact of this vulnerability is severe as it allows local attackers with minimal privileges to manipulate the ThemeStore application's file system. Attackers can leverage this weakness to write arbitrary files to the application's sandbox, potentially leading to persistent malware installation, data exfiltration, or further privilege escalation attacks. The sandbox environment typically provides isolation between applications, but this vulnerability undermines that security boundary by allowing unauthorized file operations within the targeted application's restricted space. This represents a direct violation of the principle of least privilege and can enable attackers to compromise the integrity of the application and its data.
Mitigation strategies should focus on implementing proper intent verification mechanisms within the broadcast receiver component. Developers must ensure that all incoming broadcasts are validated against expected senders and that parameters are thoroughly checked before any file operations are executed. The fix should include implementing signature verification, sender identity validation, and parameter sanitization checks. Additionally, the application should enforce strict access controls and limit the permissions granted to broadcast receivers. This vulnerability demonstrates the importance of following secure coding practices as outlined in the OWASP Mobile Top 10 and aligns with ATT&CK technique T1068 which covers local privilege escalation through improper input validation. Organizations should immediately update to version 5.3.05.2 or later and conduct thorough security reviews of all broadcast receiver implementations within their applications to prevent similar issues from occurring in other components.