CVE-2019-2124 in Android
Summary
by MITRE
In ComposeActivityEmailExternal of ComposeActivityEmailExternal.java in Android 7.1.1, 7.1.2, 8.0, 8.1 and 9, there is a possible way to silently attach files to an email due to a confused deputy. This could lead to local information disclosure.
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Analysis
by VulDB Data Team • 12/13/2023
The vulnerability identified as CVE-2019-2124 resides within the Android email composition functionality, specifically in the ComposeActivityEmailExternal component. This flaw affects multiple Android versions including 7.1.1, 7.1.2, 8.0, 8.1, and 9, creating a persistent security risk across a significant portion of the Android ecosystem. The vulnerability stems from a confused deputy problem that allows malicious applications to exploit the email composition process and silently attach files to outgoing emails without user awareness or consent.
The technical implementation of this vulnerability occurs through improper validation of inter-process communication mechanisms within the Android framework. When a user attempts to compose an email through the external email composition interface, the system fails to properly verify the authenticity and intent of the requesting application. This confusion between legitimate and malicious actors enables an attacker to manipulate the file attachment process, allowing unauthorized file inclusion in email messages. The flaw operates at the system level where the email composition service does not adequately authenticate the source of file attachment requests, creating a pathway for privilege escalation through confused deputy attacks.
The operational impact of CVE-2019-2124 extends beyond simple information disclosure, as it enables covert data exfiltration through email channels. Attackers can exploit this vulnerability to silently attach sensitive files to emails without user knowledge, potentially compromising confidential data, personal information, or corporate secrets. The silent nature of the attack makes detection extremely difficult, as users remain unaware that their files are being attached to outgoing messages. This vulnerability particularly affects enterprise environments where email remains a primary communication channel, potentially leading to significant data breaches or intellectual property theft.
Mitigation strategies for CVE-2019-2124 should prioritize immediate system updates and patches provided by Android security teams. Organizations must ensure all affected devices receive the latest security updates, as Google released patches addressing this confused deputy vulnerability. Network monitoring solutions should be enhanced to detect anomalous email attachment patterns that could indicate exploitation attempts. Security professionals should implement application whitelisting policies to restrict which applications can interact with email composition services, reducing the attack surface. Additionally, user education regarding suspicious email behaviors and regular security audits of email systems can help identify potential exploitation attempts. This vulnerability aligns with CWE-284, which describes improper access control issues, and maps to ATT&CK technique T1059.007 for command and scripting interpreter usage in email contexts, emphasizing the need for comprehensive endpoint protection strategies.