CVE-2023-1786: sensitive data exposure in cloud-init logs

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-04-26 · updated 2026-06-17
Weakness: CWE-532

Description

Sensitive data could be exposed in logs of cloud-init before version 23.1.2. An attacker could use this information to find hashed passwords and possibly escalate their privilege.

Affected products

Canonical Ltd. cloud-init: before 23.1.2 — fixed in 23.1.2
Canonical Ubuntu Linux: 16.04, 18.04, 20.04, 22.04, 22.10, 23.04
Fedoraproject Fedora: 38

How to fix

Upgrade to a fixed version: Canonical Ltd. cloud-init 23.1.2. Check the vendor advisory for mitigations.

References

https://bugs.launchpad.net/cloud-init/+bug/2013967
https://github.com/canonical/cloud-init/commit/a378b7e4f47375458651c0972e7cd813f6fe0a6b
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ATBJSXPL2IOAD2LDQRKWPLIC7QXS44GZ/
https://ubuntu.com/security/notices/USN-6042-1
https://bugs.launchpad.net/cloud-init/+bug/2013967
https://github.com/canonical/cloud-init/commit/a378b7e4f47375458651c0972e7cd813f6fe0a6b
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ATBJSXPL2IOAD2LDQRKWPLIC7QXS44GZ/
https://ubuntu.com/security/notices/USN-6042-1

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