CVE-2020-35504

Severity: medium (CVSS 6.0 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-05-28 · updated 2026-06-17
Weakness: CWE-476

Description

A NULL pointer dereference flaw was found in the SCSI emulation support of QEMU in versions before 6.0.0. This flaw allows a privileged guest user to crash the QEMU process on the host, resulting in a denial of service. The highest threat from this vulnerability is to system availability.

Affected products

Debian Linux: 10.0
Fedoraproject Fedora: 33
QEMU: before 6.0.0 — fixed in 6.0.0

How to fix

Upgrade to a fixed version: QEMU 6.0.0. Check the vendor advisory for mitigations.

References

http://www.openwall.com/lists/oss-security/2021/04/16/3
https://bugzilla.redhat.com/show_bug.cgi?id=1909766
https://lists.debian.org/debian-lts-announce/2022/09/msg00008.html
https://security.gentoo.org/glsa/202208-27
https://security.netapp.com/advisory/ntap-20210713-0006/
https://www.openwall.com/lists/oss-security/2021/04/16/3
http://www.openwall.com/lists/oss-security/2021/04/16/3
https://bugzilla.redhat.com/show_bug.cgi?id=1909766
https://lists.debian.org/debian-lts-announce/2022/09/msg00008.html
https://security.gentoo.org/glsa/202208-27
https://security.netapp.com/advisory/ntap-20210713-0006/
https://www.openwall.com/lists/oss-security/2021/04/16/3

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