RHSA-2020:3644

Vulnerability from csaf_redhat - Published: 2020-09-08 07:58 - Updated: 2026-06-30 11:36
Summary
Red Hat Security Advisory: cloud-init security update
Severity
Low
Notes
Topic: An update for cloud-init is now available for Red Hat Enterprise Linux 8.2 Extended Update Support. Red Hat Product Security has rated this update as having a security impact of Low. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.
Details: The cloud-init packages provide a set of init scripts for cloud instances. Cloud instances need special scripts to run during initialization to retrieve and install SSH keys, and to let the user run various scripts. Security Fix(es): * cloud-init: default configuration disabled deletion of SSH host keys (CVE-2018-10896) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
Terms of Use: This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original.
CVE-2018-10896

The default cloud-init configuration included "ssh_deletekeys: 0", disabling cloud-init's deletion of ssh host keys. In some environments, this could lead to instances created by cloning a golden master or template system, sharing ssh host keys, and being able to impersonate one another or conduct man-in-the-middle attacks.

4.6 (Medium)
CVSS:3.0/AV:L/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
CWE-321 - Use of Hard-coded Cryptographic Key
Affected products
Product Identifier Version Remediation
Unresolved product id: AppStream-8.2.0.Z.EUS:cloud-init-0:18.5-12.el8_2.3.noarch —
Vendor Fix fix
Unresolved product id: AppStream-8.2.0.Z.EUS:cloud-init-0:18.5-12.el8_2.3.src —
Vendor Fix fix
Threats
Impact Low
References
To clipboard 

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            "confidentialityImpact": "LOW",
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            "privilegesRequired": "LOW",
            "scope": "CHANGED",
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            "vectorString": "CVSS:3.0/AV:L/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N",
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      ],
      "title": "cloud-init: default configuration disabled deletion of SSH host keys"
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}



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