Unisoc Modem Vulnerability Allows Remote Code Execution via Video Calls

Researchers have discovered a critical vulnerability in Unisoc modem firmware that allows attackers to gain root access to various Android devices through a video call exploit. This vulnerability affects multiple budget smartphones powered by Unisoc chipsets, including the Realme C33, Xiaomi Redmi A5, and Motorola E13. The exploit involves chaining a previously disclosed remote code execution (RCE) vulnerability with a new memory isolation weakness. Attackers can execute arbitrary code on the modem and escalate privileges to the Android kernel by sending specially crafted SIP messages during a video call. The flaw is classified as Improper Isolation of Shared Resources on System-on-a-Chip (SoC) and is tracked as CWE-1189. The SSD Secure Disclosure team, which confirmed the vulnerabilities, reported that Unisoc has not responded to their outreach for remediation. The scope of impact is significant, with millions of devices potentially affected. No vendor firmware updates have been released to address this issue as of now.

Key Points: • Unisoc modem firmware vulnerabilities allow remote code execution via video calls. • Affected devices include Realme C33, Xiaomi Redmi A5, and Motorola E13. • No vendor response or firmware updates have been issued to remediate the vulnerabilities.