When instructing cloud-init to set a random password for a new user account, versions before 21.2 would write that password to the world-readable log file /var/log/cloud-init-output.log. This could allow a local user to log in as another user.
{
"extracted_events": [
{
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},
{
"fixed": "21.2"
}
],
"cpe": "cpe:2.3:a:canonical:cloud-init:*:*:*:*:*:*:*:*",
"source": [
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]
}