Log ServerApplication · Nagios

CVE-2016-15049

MEDIUM · 5.4 CVSS v3.1 Published 2025-10-30
Fix available
A fix is available. Upgrade to 1.4.2 or later.
See remediation →
58/100
Remediation priority · Elevated
Remotely reachable

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Nagios Log Server versions prior to 1.4.2 are vulnerable to cross-site scripting (XSS) in the Dashboards section when rendering log entries in the Logs table. Untrusted log content was not safely encoded for the output context, allowing attacker-controlled data present in logs to execute script in the victim’s browser within the application origin.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

Nagios Log Server versions prior to 1.4.2 contain a stored cross-site scripting (XSS) vulnerability in the Dashboards section's Logs table. Untrusted log content is rendered without proper output encoding, allowing attackers to inject malicious JavaScript that executes in the browsers of users viewing these log entries.

MitigationUpgrade to Nagios Log Server version 1.4.2 or later. Until then, restrict access to the Dashboards/Logs functionality to trusted users only and implement output encoding for all log data displayed in the UI.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Log ServerApplication
Affected:< 1.4.2

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
Required
Scope
Changed
Confidentiality
Low
Integrity
Low
Availability
None

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Determine Nagios Log Server version
    Locate the installed Nagios Log Server version number (typically accessible via the web interface footer, About page, or package management system)
    Affected if The installed version is below 1.4.2 (e.g., 1.4.1, 1.4.0, 1.3.x, etc.)
  2. Verify Dashboards/Logs feature is accessible
    Confirm that the Dashboards section and Logs table functionality is available and enabled in the Nagios Log Server installation
    Affected if Users have access to the Dashboards/Logs interface and can view log entries through the web UI
  3. Identify log ingestion sources
    Review the log sources being fed into Nagios Log Server - check which systems, applications, or network streams are forwarding logs to the Nagios Log Server
    Affected if Log sources include untrusted or external data (such as remote syslog, WMI collectors, or logs from customer-facing systems) that could contain user-supplied content
  4. Inspect stored log content for unencoded characters
    Examine raw log entries stored in the Nagios Log Server database or displayed in the Logs table - look for log entries containing HTML, JavaScript tags, or script-related attributes that may not have been sanitized upon display
    Affected if Log entries containing characters like <script>, javascript:, onerror=, or other HTML/script elements appear in the UI without being escaped or rendered as plain text

A user is affected if their Nagios Log Server version is below 1.4.2 AND they have access to the Dashboards/Logs feature AND their system ingests log content from untrusted sources that could contain malicious script payloads.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 1.4.2 or later
Fixed in 1.4.2
Interim mitigation

Upgrade to Nagios Log Server version 1.4.2 or later. Until then, restrict access to the Dashboards/Logs functionality to trusted users only and implement output encoding for all log data displayed in the UI.

Recommended fix High confidence

1.4.2

  1. Backup your current Nagios Log Server data and configuration
  2. Download Nagios Log Server version 1.4.2 or later from the official Nagios website (www.nagios.com)
  3. Follow the official Nagios Log Server upgrade documentation for your specific installation method
  4. Apply the upgrade following the documented procedures
  5. Verify the upgrade was successful by checking the version number
  6. Test that the XSS vulnerability in the Dashboards/Logs table section is resolved by verifying log entries are properly encoded

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Log Server Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing3.0 h
  • Review / QA1.0 h
10.0 hours of engineering $1,750
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,800.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2016-15049 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2016-15049 in production — separate from our analysis above.

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data