CVE-2026-63418

Name	CVE-2026-63418
Description	Monitoring Plugins is a suite of plugins for monitoring applications. From 3.0.0-rc1 until 3.0.1, check_icmp stores the number of hosts supplied through -H or --Host on the command line, or through --extra-opts files containing Host= entries, in an unsigned short. More than 65,535 hosts wrap the counter, causing process_arguments() to allocate an undersized hosts array and then write subsequent entries out of bounds before main() calls setuid(getuid()). On installations where check_icmp is setuid root, a local low-privileged attacker can corrupt heap memory while the process still has root privileges; reliable privilege escalation has not been demonstrated. Installations that use cap_net_raw file capabilities instead of setuid are not exposed to the privilege-escalation consequence. This issue is fixed in version 3.0.1.
Source	CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
monitoring-plugins (PTS)	bookworm	2.3.3-5+deb12u2	fixed
	trixie	2.4.0-3+deb13u1	fixed
	forky	2.4.0-5	fixed
	sid	3.0.3+ds-1	fixed

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
monitoring-plugins	source	(unstable)	(not affected)

Notes

- monitoring-plugins <not-affected> (Vulnerable code introduced later)
https://github.com/monitoring-plugins/monitoring-plugins/security/advisories/GHSA-xvvw-4j77-rp7q
Fixed by: https://github.com/monitoring-plugins/monitoring-plugins/commit/c35c12e58d326ffbd6cfb3c9097653f9f3fb2f4a (v3.0.1)