CVE-2026-48554
Nagios Core / XI Authenticated RCE via Unfiltered NOTIFICATION-Family Macro Substitution
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
7.7
Nagios Core / XI Authenticated RCE via Unfiltered NOTIFICATION-Family Macro Substitution
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.
- Record
CVE-2026-48554- CVSS 4.0
- 7.7 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-78
- Updated
- 2026-11-02
EUVDEUVD-2026-57346
7.7
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.
- Record
EUVD-2026-57346- CVSS 4.0
- 7.7 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-f3vr-3658-6fxw
7.7
Nagios Core before 4.5.14 and Nagios XI before 2026R1.7 are vulnerable to authenticated remote...
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.
- Record
GHSA-f3vr-3658-6fxw- CVSS 4.0
- 7.7 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-78
- Updated
- 2026-11-02
NVD
7.7
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.
- Record
CVE-2026-48554- CVSS 4.0
- 7.7 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-78
- Updated
- 2026-11-02
OSV
7.7
Nagios Core / XI Authenticated RCE via Unfiltered NOTIFICATION-Family Macro Substitution
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.
- Record
CVE-2026-48554- CVSS 4.0
- 7.7 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - Weakness
- CWE-78
- Updated
- 2026-11-02
OSVDEBIAN-CVE-2026-48554
7.7
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.
- Record
DEBIAN-CVE-2026-48554- CVSS 4.0
- 7.7 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-48554
7.7
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.
- Record
UBUNTU-CVE-2026-48554- CVSS 4.0
- 7.7 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
nagios4Debian:12 |
before 4.4.6-4+deb12u2, plus listed versions 4.4.6-44.4.6-4+deb12u1 |
4.4.6-4+deb12u2 |
nagios4Debian:13 |
before 4.4.6-4.1+deb13u2, plus listed versions 4.4.6-4.14.4.6-4.1+deb13u1 |
4.4.6-4.1+deb13u2 |
nagios4Debian:14 |
before 4.5.14+ds-1, plus listed versions 4.4.6-4.14.5.12+ds-1 |
4.5.14+ds-1 |
nagios4Ubuntu:20.04:LTS |
All versions, plus listed versions 4.3.4-34.3.4-3ubuntu0.1 |
None known |
nagios4Ubuntu:22.04:LTS |
All versions, plus listed versions 4.4.6-44.4.6-4ubuntu0.22.04.1 |
None known |
nagios4Ubuntu:24.04:LTS |
All versions, plus listed versions 4.4.6-44.4.6-4ubuntu0.24.04.1 |
None known |
nagios4Ubuntu:26.10 |
All versions, plus listed versions 4.4.6-4.1ubuntu2 |
None known |
nagios4Ubuntu:26.04:LTS |
All versions, plus listed versions 4.4.6-4.1ubuntu14.4.6-4.1ubuntu2 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-48554 is a high vulnerability (CVSS 7.7) in Nagios Enterprises Xi, published August 12, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.97%, the 61st percentile. Fixed in nagios4 4.4.6-4+deb12u2.
References
nagios.com/security-disclosures/nagios-core
github.com/NagiosEnterprises/nagioscore/blob/master/Changelog
vulncheck.com/advisories/nagios-core-xi-authenticated-rce-via-unfiltered-notification-family-macro-substitution
nvd.nist.gov/vuln/detail/CVE-2026-48554
github.com/advisories/GHSA-f3vr-3658-6fxw
github.com/CVEProject/cvelistV5/tree/main/cves/2026/48xxx/CVE-2026-48554.json
security-tracker.debian.org/tracker/CVE-2026-48554
ubuntu.com/security/CVE-2026-48554
cve.org/CVERecord?id=CVE-2026-48554