CVE-2021-4147
CWE-667Published: March 25, 2022· Updated: Jun 17, 2026
Official Description
A flaw was found in the libvirt libxl driver. A malicious guest could continuously reboot itself and cause libvirtd on the host to deadlock or crash, resulting in a denial of service condition.
Technical Analysis
CVE-2021-4147 requires local access, meaning attackers must already have a foothold on the target system.
Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
A successful exploit results in availability disruption (denial of service), with a CVSS base score of 6.5.
The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
Official Patches & Advisories
All References (6)
Quick Facts
Related CVEs (CWE-667)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2021-4147 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts