CVE-2021-20196
MEDIUMQEMU - Denial of Service via Floppy Disk Emulator NULL Pointer Dereference
Title source: llmDescription
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.
References (5)
Core 5
Core References
Exploit, Patch, Third Party Advisory x_refsource_misc
https://bugs.launchpad.net/qemu/+bug/1912780
Mailing List, Patch, Third Party Advisory x_refsource_misc
https://www.openwall.com/lists/oss-security/2021/01/28/1
Third Party Advisory x_refsource_confirm
https://security.netapp.com/advisory/ntap-20210708-0004/
Mailing List, Third Party Advisory mailing-list
x_refsource_mlist
https://lists.debian.org/debian-lts-announce/2022/04/msg00002.html
Mailing List, Third Party Advisory mailing-list
x_refsource_mlist
https://lists.debian.org/debian-lts-announce/2022/09/msg00008.html
Scores
CVSS v3
6.5
EPSS
0.0004
EPSS Percentile
11.8%
Attack Vector
LOCAL
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H
Details
CWE
CWE-476
Status
published
Products (3)
debian/debian_linux
9.0
debian/debian_linux
10.0
qemu/qemu
5.2.0
Published
May 26, 2021
Tracked Since
Feb 18, 2026