CVE-2019-11836 in Rediffmail App
Summary
by MITRE
The Rediffmail (aka com.rediff.mail.and) application 2.2.6 for Android has cleartext mail content in file storage, persisting after a logout.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 09/15/2023
The vulnerability identified as CVE-2019-11836 represents a critical security flaw in the Rediffmail Android application version 2.2.6 which exposes sensitive user data through improper data handling practices. This issue manifests when the application stores email content in cleartext format within the device's file storage system, creating a persistent security risk that remains accessible even after users have logged out of their accounts. The flaw directly violates fundamental security principles regarding data protection and user privacy, as it allows unauthorized access to confidential information through simple file system inspection.
The technical implementation of this vulnerability stems from inadequate secure storage mechanisms within the application's architecture. When users compose, receive, or interact with email content, the application fails to properly encrypt or obfuscate this data before persisting it to local storage. This cleartext storage approach creates a persistent data repository that remains accessible to any process or user with sufficient privileges to access the device's file system. The vulnerability specifically impacts the application's session management and data persistence mechanisms, where temporary or cached email content is written to disk without proper encryption or access controls. This flaw aligns with CWE-312, which addresses the exposure of sensitive information through cleartext storage, and demonstrates poor adherence to secure coding practices recommended by the OWASP Mobile Security Project.
The operational impact of this vulnerability extends beyond simple data exposure to encompass significant privacy and security risks for users of the Rediffmail application. Attackers with physical access to an infected device or those who have gained unauthorized access through other means can directly retrieve cached email content, personal information, and potentially sensitive business communications. The persistence of this data after logout operations creates a window of opportunity for unauthorized access that persists even when users believe they have properly secured their session. This vulnerability particularly affects users who may be using shared or compromised devices, as the cleartext data remains available to subsequent users or attackers who gain access to the device. The risk is compounded by the fact that email content often contains personally identifiable information, confidential business data, and other sensitive material that could be exploited for identity theft, financial fraud, or corporate espionage.
Organizations and users should implement immediate mitigations to address this vulnerability through multiple layers of protection. The primary recommendation involves application developers implementing proper encryption mechanisms for all locally stored data, particularly email content and user session information. This includes utilizing platform-specific secure storage APIs, implementing robust key management practices, and ensuring that all sensitive data is encrypted before being written to persistent storage. Additionally, developers should implement proper session cleanup procedures that explicitly remove all cached data and temporary files upon logout operations. System administrators should consider implementing device encryption policies and mobile device management solutions to provide additional protection layers. The vulnerability also highlights the importance of regular security testing and code reviews to identify similar issues in other applications, aligning with ATT&CK technique T1552.001 which addresses credentials in files and T1552.006 for data from cloud storage. Users should be educated about the risks of using applications with such vulnerabilities and the importance of proper device security measures including screen locks and encryption.