PT-2021-7363 · Qemu+9 · Qemu+9

Gaoning Pan · Published 2021-01-22 · Updated 2026-06-09 · CVE-2021-20196

Positive Technologies (AI Summary)

CVSS v3.1

6.5

Medium

Base vector

AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H

Name of the Vulnerable Software and Affected Versions QEMU (affected versions not specified)

Description The issue is related to a NULL pointer dereference flaw in the floppy disk emulator of QEMU. This flaw occurs when processing read/write ioport commands if the selected floppy drive is not initialized with a block device. It allows a privileged guest user to crash the QEMU process on the host, resulting in a denial of service. The highest threat from this issue is to system availability.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Exploit

DoS

NULL Pointer Dereference

Weakness Enumeration

CWE-476

Related Identifiers

ALSA-2022:1759

ALT-PU-2021-1767

ALT-PU-2021-3585

ALT-PU-2022-1412

ALT-PU-2022-3390

BDU:2022-05784

CESA-2022_1759

CVE-2021-20196

DLA-2970-1

DLA-3099-1

OESA-2022-1662

OPENSUSE-SU-2022:0177-1

OPENSUSE-SU-2022:0210-1

OPENSUSE-SU-2022_0177-1

OPENSUSE-SU-2022_0210-1

OPENSUSE-SU-2022_0210-2

RHSA-2022:0325

RHSA-2022:0397

RHSA-2022:1759

RHSA-2022_1759

RLSA-2022:1759

SUSE-SU-2022:0177-1

SUSE-SU-2022:0210-1

SUSE-SU-2022:0210-2

SUSE-SU-2022:1151-1

SUSE-SU-2022_0177-1

SUSE-SU-2022_1151-1

USN-5307-1

USN-8412-1

Affected Products

Alt Linux

Almalinux

Astra Linux

Centos

Linuxmint

Qemu

Red Hat

Rocky Linux

Suse

Ubuntu

References · 265

• 🔥 https://bugs.launchpad.net/qemu/+bug/1912780 · Exploit
• https://ubuntu.com/security/notices/USN-5307-1 · Vendor Advisory
• https://ubuntu.com/security/CVE-2020-15863 · Vendor Advisory
• https://ubuntu.com/security/CVE-2020-15469 · Vendor Advisory
• https://osv.dev/vulnerability/USN-5307-1 · Vendor Advisory
• https://osv.dev/vulnerability/USN-8412-1 · Vendor Advisory
• https://ubuntu.com/security/CVE-2021-20221 · Vendor Advisory
• https://openwall.com/lists/oss-security/2021/01/28/1 · Patch
• https://wiki.astralinux.ru/astra-linux-se47-bulletin-2022-0926SE47 · Vendor Advisory
• https://ubuntu.com/security/CVE-2021-4158 · Vendor Advisory
• https://osv.dev/vulnerability/openSUSE-SU-2022:0210-1 · Vendor Advisory
• https://ubuntu.com/security/CVE-2020-11947 · Vendor Advisory
• https://ubuntu.com/security/CVE-2023-3354 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2021-4206 · Security Note
• https://ubuntu.com/security/CVE-2020-35505 · Vendor Advisory