CVE-2019-20542

Vulnerability

A stack overflow vulnerability exists in the kernel driver of Samsung mobile devices with N(7.1), O(8.x), and P(9.0) software and Exynos chipsets [1]. The issue is identified by Samsung ID SVE-2019-15034 and was disclosed in November 2019 [1]. Affected versions include all builds based on Android 7.1, 8.x, and 9.0 using Exynos chipsets [1].

Exploitation

An attacker must have local access to the device and the ability to execute code with unprivileged (or limited) user context. The overflow is triggered by passing a crafted input to the vulnerable kernel driver, causing memory corruption that disrupts the driver's normal execution flow [1]. No user interaction beyond running the exploit is required [1].

Impact

A successful exploit of the stack overflow allows the attacker to escalate privileges from an unprivileged context to kernel-level execution, leading to full compromise of the device's confidentiality, integrity, and availability [1]. The attacker gains the ability to execute arbitrary code with kernel privileges, bypassing security mechanisms [1].

Mitigation

Samsung addressed this issue in its monthly security update release, likely in November 2019 or later, as per the SVE identifier [1]. Users should update their devices to the latest firmware via Samsung's security patch process. If patching is not possible, no workaround is publicly documented; the device remains vulnerable until the update is applied [1].