SB2021032302 - Multiple vulnerabilities in Canonical cloud-init
Published: March 23, 2021
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 3 secuirty vulnerabilities.
1) Use of insufficiently random values (CVE-ID: CVE-2020-8631)
The vulnerability allows a local user to predict passwords.
The vulnerability exists due to cloud-init relies on Mersenne Twister for a random password, which uses the random.choice() function in rand_str() in cloudinit/util.py. A local user can guess randomly generated passwords and gain unauthorized access.
2) Insufficiently protected credentials (CVE-ID: CVE-2020-8632)
The vulnerability allows a local user to guess passwords.
The vulnerability exists due to cloud-init has a small default pwlen value in rand_user_password() function in cloudinit/config/cc_set_passwords.py. A local user can guess passwords and gain unauthorized access to the application.
3) Inclusion of Sensitive Information in Log Files (CVE-ID: CVE-2021-3429)
The vulnerability allows a local user to gain access to sensitive information.
The vulnerability exists due to cloud-init writes randomly generated passwords as part of the chpasswd module into log files. A local user can read the log files and gain access to sensitive data.
Remediation
Install update from vendor's website.
References
- http://lists.opensuse.org/opensuse-security-announce/2020-03/msg00042.html
- https://bugs.launchpad.net/ubuntu/+source/cloud-init/+bug/1860795
- https://github.com/canonical/cloud-init/pull/204
- https://lists.debian.org/debian-lts-announce/2020/02/msg00021.html
- https://github.com/canonical/cloud-init/pull/189
- https://alas.aws.amazon.com/ALAS-2021-1486.html