Denial of service in QEMU

Published: 2021-12-22
Risk Medium
Patch available YES
Number of vulnerabilities 1
CVE-ID CVE-2021-20257
Exploitation vector Network
Public exploit N/A
Vulnerable software
Client/Desktop applications / Virtualization software

Vendor QEMU

Security Bulletin

This security bulletin contains one medium risk vulnerability.

1) Infinite loop

EUVDB-ID: #VU59085

Risk: Medium


CVE-ID: CVE-2021-20257

CWE-ID: CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')

Exploit availability: No


The vulnerability allows a remote user to perform a denial of service (DoS) attack.

The vulnerability exists due to infinite loop in the e1000 NIC emulator when processing transmits (tx) descriptors in process_tx_desc of QEMU. A remote user can consume all available CPU resources and cause denial of service conditions.


Install updates from vendor's website.

Vulnerable software versions

QEMU: 6.0.0 - 6.1.0

CPE2.3 External links

Q & A

Can this vulnerability be exploited remotely?

How the attacker can exploit this vulnerability?

Is there known malware, which exploits this vulnerability?