CVE-2020-9252

Vulnerability

CVE-2020-9252 is a path traversal vulnerability in certain Huawei smartphones. The system does not sufficiently validate a pathname from a specific process, allowing an attacker to write files to a crafted path. The affected products include HUAWEI Mate 20 (versions earlier than 10.1.0.160(C00E160R3P8)), HUAWEI Mate 20 X (versions earlier than 10.1.0.135(C00E135R2P8)), HUAWEI Mate 20 RS (versions earlier than 10.1.0.160(C786E160R3P8)), and Honor Magic2 smartphones (versions earlier than 10.1.0.160(C00E160R2P11)) [1].

Exploitation

The vulnerability can be exploited by a local attacker with access to the affected process. No authentication is required beyond local access. The attacker would need to craft a pathname that passes through the insufficient validation checks, enabling file writes to unintended locations. The exact sequence of steps is not detailed in the available references, but the flaw lies in a specific process that does not properly sanitize pathname inputs [1].

Impact

Successful exploitation allows the attacker to write files to a crafted path on the device. This could lead to arbitrary file write, potentially enabling further compromise such as overwriting system files or placing malicious files in privileged locations. The impact is limited to file write operations; the attacker does not gain remote code execution or read access directly from this vulnerability [1].

Mitigation

Huawei has released software updates to fix this vulnerability. The resolved versions are: HUAWEI Mate 20 at 10.1.0.160(C00E160R3P8), HUAWEI Mate 20 X at 10.1.0.135(C00E135R2P8), HUAWEI Mate 20 RS at 10.1.0.160(C786E160R3P8), and Honor Magic2 at 10.1.0.160(C00E160R2P11) [1]. Users should update their devices to these versions or later. No workarounds are mentioned in the advisory; applying the update is the recommended mitigation.