CVE-2019-20600 in Samsung
Summary
by MITRE
An issue was discovered on Samsung mobile devices with O(8.0) and P(9.0) (Exynos8890 chipsets) software. A use-after-free occurs in the MALI GPU driver. The Samsung ID is SVE-2019-13921-1 (May 2019).
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Analysis
by VulDB Data Team • 10/04/2020
The vulnerability identified as CVE-2019-20600 represents a critical use-after-free flaw within the MALI GPU driver component of Samsung's mobile device ecosystem. This issue specifically affects devices equipped with Exynos8890 chipsets running Android operating systems version 8.0 (Oreo) and 9.0 (Pie). The flaw manifests in the graphics processing unit driver layer, where improper memory management leads to potentially exploitable conditions that could compromise device security and stability. The vulnerability was officially acknowledged by Samsung under their internal tracking system as SVE-2019-13921-1, indicating the severity and scope of the issue within their security framework.
The technical root cause of this vulnerability stems from improper memory deallocation practices within the MALI GPU driver implementation. When certain graphics operations are performed, the driver fails to properly manage memory references, creating situations where freed memory locations are accessed after being deallocated. This use-after-free condition occurs during GPU command processing and buffer management operations, where the driver does not adequately validate memory state before subsequent operations. The flaw specifically affects the GPU's memory management subsystem, where buffer pointers are not properly invalidated after deallocation, allowing for potential memory corruption scenarios that can be exploited by malicious actors.
The operational impact of this vulnerability extends beyond simple system instability, presenting significant security risks to affected Samsung devices. An attacker could potentially leverage this use-after-free condition to execute arbitrary code within the GPU driver context, which would provide elevated privileges and access to sensitive system resources. The compromised GPU driver environment could enable attackers to bypass normal security boundaries, access protected memory regions, or manipulate graphics processing operations to gain unauthorized system access. This vulnerability represents a serious concern for mobile device security, as GPU drivers typically operate with high privileges and can serve as attack vectors for broader system compromise.
Mitigation strategies for this vulnerability should focus on both immediate patch deployment and operational security measures. Samsung released security updates addressing this specific flaw in their regular security patches, requiring users to install the latest firmware updates to remediate the issue. System administrators should prioritize immediate deployment of these patches across all affected devices, particularly in enterprise environments where mobile device security is paramount. Additionally, monitoring for anomalous GPU driver behavior or unexpected system crashes can help identify potential exploitation attempts. The vulnerability aligns with CWE-416, which specifically addresses use-after-free conditions in software implementations. From an ATT&CK framework perspective, this vulnerability could be categorized under privilege escalation techniques, as it allows for code execution within a high-privilege driver context. Organizations should implement comprehensive device management policies that ensure timely patch deployment and maintain awareness of similar vulnerabilities within their mobile device fleets to prevent potential exploitation.