CVE-2017-18147

Vulnerability

The vulnerability resides in the MMCP (Mobile Modem Control Protocol) component of Qualcomm's firmware, as used in Android for MSM, Firefox OS for MSM, and QRD Android with all Android releases from CAF using the Linux kernel before security patch level 2018-04-05. The issue is that a downlink message is not properly validated [1]. This could allow an attacker to craft a malicious message that triggers unexpected behavior in the modem processor.

Exploitation

An attacker with the ability to send a crafted downlink message to the device (likely requiring proximity to the cellular network or a compromised base station) can exploit the missing validation. No authentication or user interaction is required on the target device, as the message is processed at the modem level before reaching the Android operating system.

Impact

Successful exploitation could lead to arbitrary code execution or denial of service on the modem processor, potentially allowing the attacker to escalate privileges or disrupt cellular services. The impact is primarily on the confidentiality, integrity, and availability of the modem's processing.

Mitigation

Google's April 2018 Android Security Bulletin includes a patch for this vulnerability, released on 2018-04-01 [1]. Users should ensure their device has received the Android security patch level 2018-04-05 or later. No other workarounds have been disclosed.