CVE-2026-48554

Nagios Core / XI Authenticated RCE via Unfiltered NOTIFICATION-Family Macro Substitution

HIGH
7.5
CVSS Score
Published: August 12, 2026 at 04:48 PM UTC
Updated: September 8, 2026 at 08:39 PM UTC
4 products affected across 2 vendorsNagios XINagios CoreNagios XI

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Severity
HIGH7.5
Exploit prediction
EPSS 1.0%
SSVC
No known exploit

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 4.5.14
Affected range stops below 4.5.14, so it looks safe — our inference, not a vendor statement
v < 2026r1.7
Affected range stops below 2026r1.7, so it looks safe — our inference, not a vendor statement
v < 4.5.14
Affected range stops below 4.5.14, so it looks safe — our inference, not a vendor statement
v < 2026R1.7
Affected range stops below 2026R1.7, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCNo known exploitNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.5HIGHVulnCheck
Attack Vector
NETWORK
Complexity
HIGH
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Vector?

Quick Info

StatusAWAITING ANALYSIS
CWE
CWE-78

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