The default cloud-init configuration, in cloud-init 0.6.2 and newer, 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.
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-10896
Source: MITRE
Published: 2018-08-01
Updated: 2023-02-13
Type: CWE-321
Base Score: 3.6
Vector: AV:L/AC:L/Au:N/C:P/I:P/A:N
Impact Score: 4.9
Exploitability Score: 3.9
Severity: LOW
Base Score: 7.1
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Impact Score: 5.2
Exploitability Score: 1.8
Severity: HIGH