Disclosure Date 2021/01/03


Linux Kernel io_uring Use-After-Free Privilege Escalation Vulnerability

Linux Kernel における解放済みメモリの使用に関する脆弱性


Ryota Shiga (@Ga_ryo_)


Linux Kernel: v5.6 to v5.10.1


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

The specific flaw exists within the handling of file descriptors in io_uring. The issue results from the lack of validating the existence of an object prior to performing 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-21-001/