CVE-2020-35517: High severity qemu vulnerability

Published Jan 13, 2021
·
Updated

A flaw was found in qemu. A host privilege escalation issue was found in the virtio-fs shared file system daemon where a privileged guest user is able to create a device special file in the shared directory and use it to r/w access host devices.

Other sources

A potential host privilege escalation issue was found in the virtio-fs shared file system daemon (virtiofsd) of the QEMU. Virtio-fs daemon shares host directory tree with a guest VM. The said privilege escalation scenario may occur if a privileged guest user was to create device special file in the shared directory and use it to r/w access host devices. A privileged guest user may use this flaw to arbitrarily access (r/w) host files resulting in DoS scenario or may potentially reach privilege escalation on the host.

Upstream patch: --------------- -> https://lists.gnu.org/archive/html/qemu-devel/2021-01/msg05461.html

Red Hat

Affected Software

2 affected componentsFixes available
Qemu Qemu>=5.0.0<=5.2.50
debian/qemu
1:5.2+dfsg-11+deb11u31:5.2+dfsg-11+deb11u21:7.2+dfsg-7+deb12u121:10.0.0~rc2+ds-21:10.0.0~rc3+ds-2

Event History

Jan 13, 2021
Data Sourced
via Red Hat·01:43 PM
DescriptionSeverityAffected Software
Jan 28, 2021
CVE Published
via MITRE·07:13 PM
Data Sourced
via MITRE·07:13 PM
DescriptionWeakness
Jan 11, 2024
Data Sourced
via Launchpad·11:50 PM
Description
Sep 16, 2024
Data Sourced
via Ubuntu·02:27 AM
RemedyDescriptionSeverityAffected Software
Mar 31, 2025
Data Sourced
via Debian·01:07 AM
DescriptionAffected Software

Frequently Asked Questions

1

What is CVE-2020-35517?

CVE-2020-35517 is a vulnerability in qemu that allows a privileged guest user to create a device special file in the shared directory and use it to read/write access host devices, leading to a host privilege escalation.

2

What is the severity of CVE-2020-35517?

The severity of CVE-2020-35517 is high with a CVSS score of 8.2.

3

How does CVE-2020-35517 affect QEMU?

CVE-2020-35517 affects QEMU versions 5.0.0 to 5.2.50 and potentially allows a privileged guest user to gain host privilege by creating a device special file in the shared directory.

4

How can I fix CVE-2020-35517 on Ubuntu?

To fix CVE-2020-35517 on Ubuntu, update the `qemu` package to version 1:5.2+dfsg-6ubuntu2 or later.

5

How can I fix CVE-2020-35517 on Debian?

To fix CVE-2020-35517 on Debian, update the `qemu` package to the latest available version.

Contact

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