Disclosure Date 2021/02/09
QEMU Plan 9 File System Time-Of-Check Time-Of-Use Privilege Escalation Vulnerability
QEMU Plan9 File SystemのTime-of-check Time-of-use(TOCTOU)競合状態による権限昇格の脆弱性
This vulnerability allows local attackers to execute arbitrary code on affected installations of QEMU. An attacker must first obtain the ability to execute high-privileged code on the target guest system in order to exploit this vulnerability.
The specific flaw exists within the handling of file descriptor maps. The issue results from the lack of proper locking when performing operations on an object. An attacker can leverage this vulnerability to escalate privileges and execute code in the context of the hypervisor. https://www.zerodayinitiative.com/advisories/ZDI-21-159/