CVE-2020-16843

Name: CVE-2020-16843
Creator: NVD / NIST
Published: 2020-08-04T20:15:12.43+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.9/10EPSS 1.67%

Last modified Jun 17, 2026

CVE-2020-16843 is a medium-severity vulnerability rated 5.9/10 on the CVSS scale. In Firecracker 0.20.x before 0.20.1 and 0.21.x before 0.21.2, the network stack can freeze under heavy ingress traffic. This can result in a denial of service on the microVM when it is configured with a single network interface, and an availability problem for the microVM network interface on which the issue is triggered.. EPSS estimates a 1.67% chance of exploitation in the next 30 days.

Description

In Firecracker 0.20.x before 0.20.1 and 0.21.x before 0.21.2, the network stack can freeze under heavy ingress traffic. This can result in a denial of service on the microVM when it is configured with a single network interface, and an availability problem for the microVM network interface on which the issue is triggered.

Metrics

CVSS 3.1

5.9/10

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

1.67%

73.9th percentile

Probability of exploitation in the next 30 days. Learn more

Affected Software

Vendor	Product	Versions
Amazon	Firecracker	0.20.0
Amazon	Firecracker	0.21.0
Amazon	Firecracker	0.21.1

References

http://www.openwall.com/lists/oss-security/2020/08/13/1Mailing List, Third Party Advisory
https://github.com/firecracker-microvm/firecracker/issues/2057Mitigation, Third Party Advisory
https://www.openwall.com/lists/oss-security/2020/08/13/1Mailing List, Third Party Advisory
http://www.openwall.com/lists/oss-security/2020/08/13/1Mailing List, Third Party Advisory
https://github.com/firecracker-microvm/firecracker/issues/2057Mitigation, Third Party Advisory
https://www.openwall.com/lists/oss-security/2020/08/13/1Mailing List, Third Party Advisory

Timeline

Published: Aug 4, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-16843?

How severe is CVE-2020-16843?

CVE-2020-16843 has a CVSS score of 5.9/10 (MEDIUM severity). The EPSS model estimates a 1.67% probability of exploitation in the next 30 days.

How do I fix CVE-2020-16843?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-16843?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST