Vulnerabilities
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CVE Vulnerabilities

CVE-2021-20196

NULL Pointer Dereference

Published: May 26, 2021 | Modified: Nov 21, 2024
CVSS 3.x
6.5
MEDIUM
Source:
NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H
CVSS 2.x
2.1 LOW
AV:L/AC:L/Au:N/C:N/I:N/A:P
RedHat/V2
RedHat/V3
3.2 LOW
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:N/I:N/A:L
Ubuntu
LOW
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Additional information
NVDhttps://nvd.nist.gov/vuln/detail/CVE-2021-20196
CWEhttps://cwe.mitre.org/data/definitions/476.html

A NULL pointer dereference flaw was found in the floppy disk emulator of QEMU. This issue occurs while processing read/write ioport commands if the selected floppy drive is not initialized with a block device. 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.

Weakness

The product dereferences a pointer that it expects to be valid but is NULL.

Affected Software

NameVendorStart VersionEnd Version
QemuQemu5.2.0 (including)5.2.0 (including)
Advanced Virtualization for RHEL 8.4.0.EUSRedHatvirt:av-8040020220110150817.522a0ee4*
Advanced Virtualization for RHEL 8.4.0.EUSRedHatvirt-devel:av-8040020220110150817.522a0ee4*
Advanced Virtualization for RHEL 8.5.0.ZRedHatvirt:av-8050020220115095224.c5368500*
Advanced Virtualization for RHEL 8.5.0.ZRedHatvirt-devel:av-8050020220115095224.c5368500*
Red Hat Enterprise Linux 8RedHatvirt-devel:rhel-8060020220408104655.d63f516d*
Red Hat Enterprise Linux 8RedHatvirt:rhel-8060020220408104655.d63f516d*
QemuUbuntubionic*
QemuUbuntudevel*
QemuUbuntuesm-infra-legacy/trusty*
QemuUbuntuesm-infra/bionic*
QemuUbuntuesm-infra/focal*
QemuUbuntuesm-infra/xenial*
QemuUbuntufocal*
QemuUbuntugroovy*
QemuUbuntuhirsute*
QemuUbuntuimpish*
QemuUbuntujammy*
QemuUbuntukinetic*
QemuUbuntulunar*
QemuUbuntumantic*
QemuUbuntunoble*
QemuUbuntuoracular*
QemuUbuntuplucky*
QemuUbuntuquesting*
QemuUbuntutrusty*
QemuUbuntutrusty/esm*
QemuUbuntuxenial*
Qemu-kvmUbuntuprecise/esm*
XenUbuntubionic*
XenUbuntufocal*
XenUbuntugroovy*
XenUbuntuhirsute*
XenUbuntuimpish*
XenUbuntukinetic*
XenUbuntulunar*
XenUbuntumantic*
XenUbuntuoracular*
XenUbuntuplucky*
XenUbuntutrusty*
XenUbuntuxenial*

Potential Mitigations

References

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