Disclosure Date 2021/10/20


Linux Kernel Bluetooth CMTP Module Double Free Privilege Escalation Vulnerability

Linux Kernel の Bluetooth CMTP モジュール上の Double Free 脆弱性による権限昇格


Ryota Shiga (@Ga_ryo_)


Linux Kernel: v5.10.41 and earlier


Note that exploiting this bug requires CAP_NET_ADMIN in init_user.

This vulnerability allows local attackers to escalate privileges on affected installations of Linux Kernel. An attacker must first obtain the ability to execute high-privileged code on the target system in order to exploit this vulnerability.

The specific flaw exists within the CMTP module. The issue results from the lack of validating the existence of an object prior to performing further free operations on the object. An attacker can leverage this vulnerability to escalate privileges and execute code in the context of the kernel. https://www.zerodayinitiative.com/advisories/ZDI-21-1223/