Nagios Core before 4.5.14 and Nagios XI before 2026R1.7 are vulnerable to authenticated remote code execution via unfiltered NOTIFICATION-family macro substitution through the com_data parameter. When a notification command references $NOTIFICATIONCOMMENT$ or $NOTIFICATIONAUTHOR$ in a shell-reachable position, authenticated UI users can run arbitrary commands as the nagios user. Exploitation requires a non-default configuration in which a notification command references these macros in a shell-executed command line.

The remote Debian 12 host has packages installed that are affected by multiple vulnerabilities as referenced in the dla-4832 advisory.

    - -------------------------------------------------------------------------     Debian LTS Advisory DLA-4832-1                debian-lts@lists.debian.org     https://www.debian.org/lts/security/                       Russell Stuart     October 13, 2026                              https://wiki.debian.org/LTS
    - -------------------------------------------------------------------------

    Package        : nagios4     Version        : 4.4.6-4+deb12u2     CVE ID         : CVE-2026-48549 CVE-2026-48550 CVE-2026-48551 CVE-2026-48552                      CVE-2026-48553 CVE-2026-48554

    Multiple security vulnerabilities were discovered in the Nagios     monitoring system, which could result in cross-site request forgery,     cross-site scripting or the execution of arbitrary commands.

    For Debian 12 bookworm, these problems have been fixed in version     4.4.6-4+deb12u2.

    We recommend that you upgrade your nagios4 packages.

    For the detailed security status of nagios4 please refer to     its security tracker page at:
    https://security-tracker.debian.org/tracker/nagios4

    Further information about Debian LTS security advisories, how to apply     these updates to your system and frequently asked questions can be     found at: https://wiki.debian.org/LTS

Tenable has extracted the preceding description block directly from the Debian security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote Debian 13 host has packages installed that are affected by multiple vulnerabilities as referenced in the dsa-6556 advisory.

    - -------------------------------------------------------------------------     Debian Security Advisory DSA-6556-1                   security@debian.org     https://www.debian.org/security/                       Moritz Muehlenhoff     October 12, 2026                      https://www.debian.org/security/faq
    - -------------------------------------------------------------------------

    Package        : nagios4     CVE ID         : CVE-2026-48549 CVE-2026-48550 CVE-2026-48551                      CVE-2026-48552 CVE-2026-48553 CVE-2026-48554

    Multiple security vulnerabilities were discovered in the Nagios     monitoring system, which could result in cross-site request forgery,     cross-site scripting or the execution of arbitrary commands.

    For the stable distribution (trixie), these problems have been fixed in     version 4.4.6-4.1+deb13u2.

    We recommend that you upgrade your nagios4 packages.

    For the detailed security status of nagios4 please refer to     its security tracker page at:
    https://security-tracker.debian.org/tracker/nagios4

    Further information about Debian Security Advisories, how to apply     these updates to your system and frequently asked questions can be     found at: https://www.debian.org/security/

    Mailing list: debian-security-announce@lists.debian.org

Tenable has extracted the preceding description block directly from the Debian security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - Nagios Core before 4.5.14 and Nagios XI before 2026R1.7 are vulnerable to authenticated remote code     execution via unfiltered NOTIFICATION-family macro substitution through the com_data parameter. When a     notification command references $NOTIFICATIONCOMMENT$ or $NOTIFICATIONAUTHOR$ in a shell-reachable     position, authenticated UI users can run arbitrary commands as the nagios user. Exploitation requires a     non-default configuration in which a notification command references these macros in a shell-executed     command line. (CVE-2026-48554)

Note that Nessus relies on the presence of the package as reported by the vendor.

ID	Name	Product	Family	Type	Severity
365334	Debian dla-4832 : nagios4 - security update	Nessus	Debian Local Security Checks	Local	high
365110	Debian dsa-6556 : nagios4 - security update	Nessus	Debian Local Security Checks	Local	high
335306	Linux Distros Unpatched Vulnerability : CVE-2026-48554	Nessus	Misc.	Local	high

Detections

Analytics

CVE-2026-48554

high

Tenable Plugins

high

high

high