DSA-6426-1 icinga2 - security update

Multiple vulnerabilities were discovered in Icinga 2, a monitoring and
alerting system, which may result in denial of service, information
disclosure, privilege escalation or the compromise of a monitoring node.

The fix for CVE-2025-61909 changes /etc/logrotate.d/icinga2, which is a
configuration file. If it was modified locally, dpkg will not replace it
and the fix will not take effect. After the upgrade, please make sure the
postrotate section is updated.

https://security-tracker.debian.org/tracker/DSA-6426-1