Medium severity · published May 26, 2021
CVE-2021-20196
A NULL pointer dereference flaw was found in the floppy disk emulator of QEMU
6.5
CVSS
0.5%
EPSS
No
On KEV
Description
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 vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 41% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
9.0; 10.0 · source: NVD
QE
Qemu · Qemu
5.2.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-20196
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-20196
Exploit
https://bugs.launchpad.net/qemu/+bug/1912780
Mailing List
https://lists.debian.org/debian-lts-announce/2022/04/msg00002.html
Mailing List
https://lists.debian.org/debian-lts-announce/2022/09/msg00008.html
Third Party Advisory
https://security.netapp.com/advisory/ntap-20210708-0004/
Mailing List
https://www.openwall.com/lists/oss-security/2021/01/28/1
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