CVE-2020-26601 in Mobile Device
Summary
by MITRE • 10/06/2020
An issue was discovered in DirEncryptService on Samsung mobile devices with O(8.x), P(9.0), and Q(10.0) software. PendingIntent with an empty intent is mishandled, allowing an attacker to perform a privileged action via a modified intent. The Samsung ID is SVE-2020-18034 (October 2020).
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Analysis
by VulDB Data Team • 11/17/2020
The vulnerability CVE-2020-26601 represents a critical privilege escalation flaw within Samsung's DirEncryptService component affecting Android versions 8.x, 9.0, and 10.0. This issue resides in the Samsung-specific encryption service that manages device-level file encryption and decryption operations. The vulnerability stems from improper handling of PendingIntent objects when they contain empty intents, creating a pathway for malicious actors to execute unauthorized privileged operations. The Samsung Security Vulnerability Enhancement program identified this weakness as SVE-2020-18034, highlighting its significance in the mobile security landscape.
The technical root cause of this vulnerability lies in the improper validation and processing of PendingIntent objects within the DirEncryptService. When the service receives a PendingIntent with an empty intent, it fails to properly validate the intent's contents or verify the calling application's authorization level. This flaw allows an attacker to craft a malicious intent that appears legitimate to the service but contains modified parameters or actions that bypass normal security checks. The vulnerability specifically targets the intent handling mechanism where the service assumes that any incoming PendingIntent, regardless of its intent content, should be processed with elevated privileges. This design flaw creates a direct path for privilege escalation attacks that can potentially compromise the entire device encryption system.
The operational impact of CVE-2020-26601 extends beyond simple privilege escalation, as it enables attackers to manipulate the device's encryption services and potentially gain access to encrypted data. An attacker exploiting this vulnerability could perform unauthorized encryption or decryption operations, modify encryption keys, or even disable the device's encryption features entirely. The attack surface is particularly concerning because DirEncryptService operates at a system level with high privileges, meaning successful exploitation could lead to complete device compromise. This vulnerability particularly affects Samsung devices running Android 8.0 through 10.0, representing a significant portion of the Android ecosystem that was vulnerable to such attacks.
From a cybersecurity perspective, this vulnerability aligns with CWE-284 (Improper Access Control) and represents a classic case of insufficient input validation in privileged system components. The flaw demonstrates how Android's permission model can be bypassed through improper PendingIntent handling, creating a vector for attacks that fall under the ATT&CK framework's privilege escalation techniques. The vulnerability's exploitation requires minimal user interaction since it can be triggered through malicious applications or system-level modifications. Security researchers have noted that this type of vulnerability is particularly dangerous because it operates within the device's core security services, making detection and prevention challenging. Organizations should implement comprehensive patch management strategies and consider device-level monitoring to detect potential exploitation attempts of this vulnerability.
Mitigation strategies for CVE-2020-26601 should prioritize immediate patch deployment from Samsung, as the vulnerability affects multiple Android versions and device models. System administrators should conduct thorough vulnerability assessments to identify affected devices and implement network-level monitoring to detect suspicious PendingIntent usage patterns. The Android security model's inherent design requires careful attention to intent handling within system services, and developers should ensure that all PendingIntent objects undergo proper validation before execution. Additionally, users should avoid installing untrusted applications and maintain regular security updates to protect against similar vulnerabilities in the future. The vulnerability underscores the importance of robust input validation and privilege separation in system-level services, particularly those handling encryption and security-critical operations.