CVE-2021-20196

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.

CVSS v3.0 6.5 MEDIUM
CVSS v2.0 2.1 LOW

6.5^/10

CVSS v3.0 : MEDIUM

Vector :

Exploitability : 2.0 / Impact : 4.0

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope CHANGED

2.1^/10

CVSS v2.0 : LOW

Vector : AV:L/AC:L/Au:N/C:N/I:N/A:P

Exploitability : 3.9 / Impact : 2.9

Access Vector LOCAL

Access Complexity LOW

Authentication NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact PARTIAL

References

Link	Resource
https://bugs.launchpad.net/qemu/+bug/1912780	Exploit Patch Third Party Advisory
https://www.openwall.com/lists/oss-security/2021/01/28/1	Mailing List Patch Third Party Advisory
https://security.netapp.com/advisory/ntap-20210708-0004/	Third Party Advisory
https://lists.debian.org/debian-lts-announce/2022/04/msg00002.html	Mailing List Third Party Advisory
https://lists.debian.org/debian-lts-announce/2022/09/msg00008.html	Mailing List Third Party Advisory

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Configurations

Configuration 1 (hide)

cpe:2.3:a:qemu:qemu:5.2.0:-:*:*:*:*:*:*

Configuration 2 (hide)

OR	cpe:2.3:o:debian:debian_linux:9.0:::::::*
	cpe:2.3:o:debian:debian_linux:10.0:::::::*

Information

Published : 2021-05-26 15:15

Updated : 2023-02-12 14:15

NVD link : CVE-2021-20196

Mitre link : CVE-2021-20196

JSON object : View

CWE

CWE-476

NULL Pointer Dereference

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Products Affected

debian

debian_linux

qemu

qemu

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