External risk intelligence

Nagios Log Server Code Injection Leading to Remote Code Execution.

CVE advisorySeverity: CRITICAL (CVSS 9.4)

CVE-2025-34277

Nagios Log Server is a centralized log management and dashboarding application. Such systems are commonly deployed as web-based interfaces accessed by administrators and teams over a network. While it is an internal tool, the nature of the application as a central management dashboard frequently leads to it being exposed as a web application within a corporate network or reachable via remote access services.

Code Injection

Nagios Log Server

before 20242024

Halo Surface Signal: 4 out of 5 — likely to be public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

A vulnerability exists in Nagios Log Server that could allow an unauthorized user to execute arbitrary code. This occurs when the system improperly handles dashboard ID values, enabling an attacker to inject malicious data. The main concern is to confirm if our environment is affected and understand the potential exposure.

Code injection flaw in log server.
Critical vulnerability allows code execution.
Assess exposure and confirm relevance.

Attack Path

How an attacker could exploit the issue

An attacker could exploit this vulnerability by submitting specially crafted dashboard IDs to Nagios Log Server. The system's failure to properly validate these IDs before sending them to an internal API allows an attacker to inject and execute arbitrary code within the context of the Log Server process.

Attackers need network access.
Crafted dashboard IDs trigger code injection.
Arbitrary code execution is possible.

Live Threat

Current exploitation, exposure, and threat context

This vulnerability could allow an unauthenticated attacker to execute arbitrary code on the Nagios Log Server when malformed dashboard IDs are processed. This could impact the integrity and availability of the log server's operations and any data it manages.

Log server process and data at risk.
Malformed dashboard IDs may trigger code execution.
System compromise and data manipulation.

Operational Fix

Recommended remediation, mitigation, and detection steps

The Nagios Log Server is a centralized logging and dashboarding tool, likely managed by infrastructure or platform teams. Its critical role in collecting and presenting security data means its owners must first identify all instances, verify their reachability and business impact, and confirm the accountable team. Remediation planning should then be prioritized based on this risk assessment, coordinating with vendor management if necessary.

Identify and confirm Nagios Log Server owners.
Verify Nagios Log Server reachability and criticality.
Plan remediation based on exposure and impact.

Supplementary metadata

CVSS vector

Validate whether this threat affects your internet-facing exposure.

Halo Threat Intelligence helps prioritize remediation with Halo Surface Signal and H/A/L/O context. Start exposure validation with a free external attack surface trial.

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Frequently asked questions

What is Nagios Log Server used for?

Nagios Log Server is a centralized log management platform that collects, stores, and analyzes log data across an organization. Teams use it to create interactive dashboards, monitor system performance, and investigate security events by visualizing massive amounts of log traffic in one place.

What does CWE-94 mean for CVE-2025-34277?

CWE-94 refers to improper control of generation of code, commonly known as code injection. In the context of this CVE, it means the application fails to scrub or validate dashboard ID values. Because the server treats this input as trusted code instead of just data, it inadvertently runs whatever commands an attacker includes within those malformed values.

How is this vulnerability triggered?

The flaw is triggered when an attacker submits a specially crafted dashboard ID to the server. The server then passes this malformed data to an internal API without checking it first. Normal dashboard usage or legitimate interactions with the web interface do not trigger this, as the vulnerability specifically requires the submission of malicious, non-standard ID values.

Is my Nagios Log Server instance at risk?

According to Halo Surface Signal, because this tool is a central management dashboard, it is often accessible throughout a corporate network or via remote access portals. If your instance is reachable over the network, it should be considered a potential target, even if the application is intended for internal use only.

What should I do if I run this software?

First, locate all running instances of Nagios Log Server and confirm the version currently installed. Since versions prior to 2024R1.3.1 are affected, compare your version against this threshold. Once you have identified the versions, coordinate with your infrastructure or platform team to plan an update to the latest secure release provided by the vendor.

References

Written by Nicholas Merritt

Nicholas Merritt is VP of Security Solutions at Halo Security. With more than 25 years across application security, vulnerability prioritization, and offensive security, he helps teams translate threat data into practical exposure validation and remediation focus. He authors Halo Threat Intelligence CVE advisories using Halo Surface Signal and H/A/L/O context to prioritize internet-facing risk.