Medium severity · published Mar 16, 2022
CVE-2021-20257
An infinite loop flaw was found in the e1000 NIC emulator of the QEMU
6.5
CVSS
0.4%
EPSS
No
On KEV
Description
An infinite loop flaw was found in the e1000 NIC emulator of the QEMU. This issue occurs while processing transmits (tx) descriptors in process_tx_desc if various descriptor fields are initialized with invalid values. This flaw allows a guest to consume CPU cycles 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)0.4% · higher than 31% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CL
Codeready Linux Builder · Redhat
All versions, or not specified · source: NVD
DL
Debian Linux · Debian
10.0 · source: NVD
EL
Enterprise Linux · Redhat
6.0; 8.0; 8.0 · source: NVD
EL
Enterprise Linux For Ibm Z Systems · Redhat
8.0 · source: NVD
EL
Enterprise Linux For Power Little Endian · Redhat
8.0 · source: NVD
FE
Fedora · Fedoraproject
33 · source: NVD
OP
Openstack Platform · Redhat
10.0; 13.0 · source: NVD
QE
Qemu · Qemu
before 6.2.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-20257
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-20257
Issue Tracking
https://bugzilla.redhat.com/show_bug.cgi?id=1930087
Patch
https://github.com/qemu/qemu/commit/3de46e6fc489c52c9431a8a832ad8170a7569bd8
Mailing List
https://lists.debian.org/debian-lts-announce/2022/09/msg00008.html
Mailing List
https://lists.gnu.org/archive/html/qemu-devel/2021-02/msg07428.html
Third Party Advisory
https://security.gentoo.org/glsa/202208-27
Third Party Advisory
https://security.netapp.com/advisory/ntap-20220425-0003/
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