# CVE-2021-4147: libvirt: A flaw was found in the libvirt libxl driver

CVE-2021-4147 is fixed in 19 products on 1 platform, first by libnss-libvirt 4.0.0-1ubuntu8.21, released March 25, 2022. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2021-4147
- Priority: Routine
- CVSS: 6.5 (medium)
- EPSS: 0.0024
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Mar 25, 2022

## 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.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | libnss-libvirt Ubuntu 18.04.6 LTS (bionic) | 4.0.0-1ubuntu8.21 | [libnss-libvirt 4.0.0-1ubuntu8.21](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libnss-libvirt-4.0.0-1ubuntu8.21.md) | Mar 25, 2022 |
| Linux | libnss-libvirt Ubuntu 20.04 LTS (focal) | 6.0.0-0ubuntu8.16 | [libnss-libvirt 6.0.0-0ubuntu8.16](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libnss-libvirt-6.0.0-0ubuntu8.16.md) | Mar 25, 2022 |
| Linux | libvirt Debian 12.15 (bookworm) | 7.10.0-2 | [DEBIAN-CVE-2021-4147](https://patchblox.com/security/data/fix/linux/debian-cve-2021-4147.md) | Mar 25, 2022 |
| Linux | libvirt Debian 13.5 (trixie) | 7.10.0-2 | [DEBIAN-CVE-2021-4147](https://patchblox.com/security/data/fix/linux/debian-cve-2021-4147.md) | Mar 25, 2022 |
| Linux | libvirt Debian 14 | 7.10.0-2 | [DEBIAN-CVE-2021-4147](https://patchblox.com/security/data/fix/linux/debian-cve-2021-4147.md) | Mar 25, 2022 |
| Linux | libvirt-bin Ubuntu 18.04.6 LTS (bionic) | 4.0.0-1ubuntu8.21 | [libvirt-bin 4.0.0-1ubuntu8.21](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libvirt-bin-4.0.0-1ubuntu8.21.md) | Mar 25, 2022 |
| Linux | libvirt-clients Ubuntu 18.04.6 LTS (bionic) | 4.0.0-1ubuntu8.21 | [libvirt-clients 4.0.0-1ubuntu8.21](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libvirt-clients-4.0.0-1ubuntu8.21.md) | Mar 25, 2022 |
| Linux | libvirt-clients Ubuntu 20.04 LTS (focal) | 6.0.0-0ubuntu8.16 | [libvirt-clients 6.0.0-0ubuntu8.16](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libvirt-clients-6.0.0-0ubuntu8.16.md) | Mar 25, 2022 |
| Linux | libvirt-daemon Ubuntu 18.04.6 LTS (bionic) | 4.0.0-1ubuntu8.21 | [libvirt-daemon 4.0.0-1ubuntu8.21](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libvirt-daemon-4.0.0-1ubuntu8.21.md) | Mar 25, 2022 |
| Linux | libvirt-daemon Ubuntu 20.04 LTS (focal) | 6.0.0-0ubuntu8.16 | [libvirt-daemon 6.0.0-0ubuntu8.16](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libvirt-daemon-6.0.0-0ubuntu8.16.md) | Mar 25, 2022 |
| Linux | libvirt-daemon-driver-lxc Ubuntu 20.04 LTS (focal) | 6.0.0-0ubuntu8.16 | [libvirt-daemon-driver-lxc 6.0.0-0ubuntu8.16](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libvirt-daemon-driver-lxc-6.0.0-0ubuntu8.16.md) | Mar 25, 2022 |
| Linux | libvirt-daemon-driver-qemu Ubuntu 20.04 LTS (focal) | 6.0.0-0ubuntu8.16 | [libvirt-daemon-driver-qemu 6.0.0-0ubuntu8.16](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libvirt-daemon-driver-qemu-6.0.0-0ubuntu8.16.md) | Mar 25, 2022 |
| Linux | libvirt-daemon-driver-storage-gluster Ubuntu 18.04.6 LTS (bionic) | 4.0.0-1ubuntu8.21 | [libvirt-daemon-driver-storage-gluster 4.0.0-1ubuntu8.21](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libvirt-daemon-driver-storage-gluster-4.0.0-1ubuntu8.21.md) | Mar 25, 2022 |
| Linux | libvirt-daemon-driver-storage-gluster Ubuntu 20.04 LTS (focal) | 6.0.0-0ubuntu8.16 | [libvirt-daemon-driver-storage-gluster 6.0.0-0ubuntu8.16](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libvirt-daemon-driver-storage-gluster-6.0.0-0ubuntu8.16.md) | Mar 25, 2022 |
| Linux | libvirt-daemon-driver-storage-rbd Ubuntu 18.04.6 LTS (bionic) | 4.0.0-1ubuntu8.21 | [libvirt-daemon-driver-storage-rbd 4.0.0-1ubuntu8.21](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libvirt-daemon-driver-storage-rbd-4.0.0-1ubuntu8.21.md) | Mar 25, 2022 |
| Linux | libvirt-daemon-driver-storage-rbd Ubuntu 20.04 LTS (focal) | 6.0.0-0ubuntu8.16 | [libvirt-daemon-driver-storage-rbd 6.0.0-0ubuntu8.16](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libvirt-daemon-driver-storage-rbd-6.0.0-0ubuntu8.16.md) | Mar 25, 2022 |
| Linux | libvirt-daemon-driver-storage-sheepdog Ubuntu 18.04.6 LTS (bionic) | 4.0.0-1ubuntu8.21 | [libvirt-daemon-driver-storage-sheepdog 4.0.0-1ubuntu8.21](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libvirt-daemon-driver-storage-sheepdog-4.0.0-1ubuntu8.21.md) | Mar 25, 2022 |
| Linux | libvirt-daemon-driver-storage-zfs Ubuntu 18.04.6 LTS (bionic) | 4.0.0-1ubuntu8.21 | [libvirt-daemon-driver-storage-zfs 4.0.0-1ubuntu8.21](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libvirt-daemon-driver-storage-zfs-4.0.0-1ubuntu8.21.md) | Mar 25, 2022 |
| Linux | libvirt-daemon-driver-storage-zfs Ubuntu 20.04 LTS (focal) | 6.0.0-0ubuntu8.16 | [libvirt-daemon-driver-storage-zfs 6.0.0-0ubuntu8.16](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libvirt-daemon-driver-storage-zfs-6.0.0-0ubuntu8.16.md) | Mar 25, 2022 |
| Linux | libvirt-daemon-driver-vbox Ubuntu 20.04 LTS (focal) | 6.0.0-0ubuntu8.16 | [libvirt-daemon-driver-vbox 6.0.0-0ubuntu8.16](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libvirt-daemon-driver-vbox-6.0.0-0ubuntu8.16.md) | Mar 25, 2022 |
| Linux | libvirt-daemon-driver-xen Ubuntu 20.04 LTS (focal) | 6.0.0-0ubuntu8.16 | [libvirt-daemon-driver-xen 6.0.0-0ubuntu8.16](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libvirt-daemon-driver-xen-6.0.0-0ubuntu8.16.md) | Mar 25, 2022 |
| Linux | libvirt-daemon-system Ubuntu 18.04.6 LTS (bionic) | 4.0.0-1ubuntu8.21 | [libvirt-daemon-system 4.0.0-1ubuntu8.21](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libvirt-daemon-system-4.0.0-1ubuntu8.21.md) | Mar 25, 2022 |
| Linux | libvirt-daemon-system Ubuntu 20.04 LTS (focal) | 6.0.0-0ubuntu8.16 | [libvirt-daemon-system 6.0.0-0ubuntu8.16](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libvirt-daemon-system-6.0.0-0ubuntu8.16.md) | Mar 25, 2022 |
| Linux | libvirt-daemon-system-systemd Ubuntu 20.04 LTS (focal) | 6.0.0-0ubuntu8.16 | [libvirt-daemon-system-systemd 6.0.0-0ubuntu8.16](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libvirt-daemon-system-systemd-6.0.0-0ubuntu8.16.md) | Mar 25, 2022 |
| Linux | libvirt-daemon-system-sysv Ubuntu 20.04 LTS (focal) | 6.0.0-0ubuntu8.16 | [libvirt-daemon-system-sysv 6.0.0-0ubuntu8.16](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libvirt-daemon-system-sysv-6.0.0-0ubuntu8.16.md) | Mar 25, 2022 |
| Linux | libvirt-sanlock Ubuntu 18.04.6 LTS (bionic) | 4.0.0-1ubuntu8.21 | [libvirt-sanlock 4.0.0-1ubuntu8.21](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libvirt-sanlock-4.0.0-1ubuntu8.21.md) | Mar 25, 2022 |
| Linux | libvirt-sanlock Ubuntu 20.04 LTS (focal) | 6.0.0-0ubuntu8.16 | [libvirt-sanlock 6.0.0-0ubuntu8.16](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libvirt-sanlock-6.0.0-0ubuntu8.16.md) | Mar 25, 2022 |
| Linux | libvirt-wireshark Ubuntu 18.04.6 LTS (bionic) | 4.0.0-1ubuntu8.21 | [libvirt-wireshark 4.0.0-1ubuntu8.21](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libvirt-wireshark-4.0.0-1ubuntu8.21.md) | Mar 25, 2022 |
| Linux | libvirt-wireshark Ubuntu 20.04 LTS (focal) | 6.0.0-0ubuntu8.16 | [libvirt-wireshark 6.0.0-0ubuntu8.16](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libvirt-wireshark-6.0.0-0ubuntu8.16.md) | Mar 25, 2022 |
| Linux | libvirt0 Ubuntu 18.04.6 LTS (bionic) | 4.0.0-1ubuntu8.21 | [libvirt0 4.0.0-1ubuntu8.21](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libvirt0-4.0.0-1ubuntu8.21.md) | Mar 25, 2022 |
| Linux | libvirt0 Ubuntu 20.04 LTS (focal) | 6.0.0-0ubuntu8.16 | [libvirt0 6.0.0-0ubuntu8.16](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libvirt0-6.0.0-0ubuntu8.16.md) | Mar 25, 2022 |

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