This morning i was awakened by multiple alarm emails sent by our zabbix agent monitoring system, telling us that /etc/passwd was being modified. The agent sent us an email for every one of our droplets (debian 9 stretch).
After the initial scare, i checked the apt logs and it seems that do-agent service was upgraded silently:
apt-get -o Dpkg::Options::=--force-confdef -o Dpkg::Options::=--force-confold -qq install -y --only-upgrade do-agent
No other alarms were going off, and everything seems to be working nominal.
I think the changes to /etc/passwd were made to the do-agent user during the upgrade process, but i would like to know from you guys if this is actually the case.
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