CVE-2021-20257

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.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.03%
Vendor Advisory gentoo.org Vendor Advisory gnu.org
Affected: n/a QEMU
Published at:
Updated at:

References

Link Tags
https://www.openwall.com/lists/oss-security/2021/02/25/2 mailing list third party advisory patch
https://lists.gnu.org/archive/html/qemu-devel/2021-02/msg07428.html mailing list patch vendor advisory
https://github.com/qemu/qemu/commit/3de46e6fc489c52c9431a8a832ad8170a7569bd8 third party advisory patch
https://bugzilla.redhat.com/show_bug.cgi?id=1930087 issue tracking third party advisory patch
https://security.netapp.com/advisory/ntap-20220425-0003/ third party advisory
https://security.gentoo.org/glsa/202208-27 third party advisory vendor advisory
https://lists.debian.org/debian-lts-announce/2022/09/msg00008.html third party advisory mailing list

Frequently Asked Questions

What is the severity of CVE-2021-20257?
CVE-2021-20257 has been scored as a medium severity vulnerability.
How to fix CVE-2021-20257?
To fix CVE-2021-20257, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-20257 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-20257 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-20257?
CVE-2021-20257 affects n/a QEMU.
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