CVE-2020-8631

Name: CVE-2020-8631
Creator: NVD / NIST
Published: 2020-02-05T14:15:11.607+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.5/10EPSS 0.44%

Last modified Jun 17, 2026

CVE-2020-8631 is a medium-severity vulnerability rated 5.5/10 on the CVSS scale. cloud-init through 19.4 relies on Mersenne Twister for a random password, which makes it easier for attackers to predict passwords, because rand_str in cloudinit/util.py calls the random.choice function.. EPSS estimates a 0.44% chance of exploitation in the next 30 days.

Description

cloud-init through 19.4 relies on Mersenne Twister for a random password, which makes it easier for attackers to predict passwords, because rand_str in cloudinit/util.py calls the random.choice function.

Metrics

CVSS 3.1

5.5/10

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

EPSS Probability

0.44%

35.0th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-330

Affected Software

Vendor	Product	Versions
Canonical	Cloud-Init	<= 19.4
Opensuse	Leap	15.1
Debian	Debian Linux	8.0

References

http://lists.opensuse.org/opensuse-security-announce/2020-03/msg00042.htmlMailing List, Third Party Advisory
https://bugs.launchpad.net/ubuntu/+source/cloud-init/+bug/1860795Issue Tracking, Patch, Third Party Advisory
https://github.com/canonical/cloud-init/pull/204Patch, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2020/02/msg00021.htmlMailing List, Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2020-03/msg00042.htmlMailing List, Third Party Advisory
https://bugs.launchpad.net/ubuntu/+source/cloud-init/+bug/1860795Issue Tracking, Patch, Third Party Advisory
https://github.com/canonical/cloud-init/pull/204Patch, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2020/02/msg00021.htmlMailing List, Third Party Advisory

Timeline

Published: Feb 5, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-8631?

How severe is CVE-2020-8631?

CVE-2020-8631 has a CVSS score of 5.5/10 (MEDIUM severity). The EPSS model estimates a 0.44% probability of exploitation in the next 30 days.

How do I fix CVE-2020-8631?

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-2020-8631?

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

Scan your code now

Source: NVD / NIST