CVE-2024-13999 Overview
CVE-2024-13999 is an information disclosure vulnerability in Nagios XI versions prior to 2024R1.1.3. Under certain conditions, the application exposes the server's Active Directory (AD) or Lightweight Directory Access Protocol (LDAP) authentication token to an authenticated user. The flaw is tracked under CWE-497: Exposure of Sensitive System Information to an Unauthorized Control Sphere.
An authenticated attacker who retrieves the token can reuse it against the directory service. This enables domain-wide authentication misuse, privilege escalation, and lateral movement into network-integrated systems that trust the same directory. The EPSS probability is approximately 1.13% at the 78.5th percentile.
Critical Impact
Exposure of the server's AD/LDAP token can allow domain-wide authentication misuse, privilege escalation, and further compromise of network-integrated systems trusting the same directory.
Affected Products
- Nagios XI 2024R1
- Nagios XI 2024R1.0.1, 2024R1.0.2
- Nagios XI 2024R1.1, 2024R1.1.1, 2024R1.1.2
Discovery Timeline
- 2025-10-30 - CVE-2024-13999 published to NVD
- 2025-11-06 - Last updated in NVD database
Technical Details for CVE-2024-13999
Vulnerability Analysis
Nagios XI integrates with external directory services to authenticate users against AD or LDAP. To bind to the directory, the server holds a service token or credential used for authentication queries. In affected releases, this token is returned through an application response path accessible to an authenticated low-privilege user.
Because the token belongs to the Nagios XI server rather than the requesting user, its disclosure breaks the trust boundary between the monitoring application and the directory infrastructure. An attacker who obtains valid Nagios XI credentials, including a low-tier account, can extract the token without triggering directory authentication failures.
Root Cause
The root cause is improper scoping of sensitive configuration data returned to authenticated sessions. The application fails to filter the AD/LDAP bind token from a response object before serializing it to the client. This matches the pattern described by CWE-497, where system-level secrets reach an unauthorized control sphere.
Attack Vector
Exploitation requires network access to the Nagios XI web interface and valid authenticated credentials. After login, the attacker reaches the vulnerable response surface that returns the AD/LDAP token. The attacker then replays that token against the directory service to authenticate as the Nagios XI service principal and query or modify directory objects within its permissions.
No verified public proof-of-concept code is available. Refer to the VulnCheck Advisory for Nagios XI for technical details.
Detection Methods for CVE-2024-13999
Indicators of Compromise
- Authenticated Nagios XI requests from low-privilege accounts to administrative or configuration endpoints that return directory integration data.
- LDAP or AD bind events from the Nagios XI service account originating from hosts other than the Nagios XI server.
- Directory queries from the Nagios XI service principal at times outside normal monitoring intervals.
Detection Strategies
- Inspect Nagios XI web access logs for repeated requests by non-administrative users to endpoints that expose directory configuration.
- Correlate domain controller authentication logs with the Nagios XI service account to identify logons from unexpected source IPs.
- Alert on directory enumeration patterns (LDAP search filters returning large object sets) tied to the Nagios XI bind identity.
Monitoring Recommendations
- Forward Nagios XI application logs and Windows or LDAP directory server logs to a centralized analytics platform for correlation.
- Track the Nagios XI service account for any interactive logons, Kerberos ticket requests, or password changes.
- Baseline normal LDAP query volume from the Nagios XI host and alert on deviations.
How to Mitigate CVE-2024-13999
Immediate Actions Required
- Upgrade Nagios XI to version 2024R1.1.3 or later as documented in the Nagios XI Changelog.
- Rotate the AD/LDAP service account credential used by Nagios XI on the assumption that the token may already be exposed.
- Audit Nagios XI user accounts and remove unused or low-trust authenticated users.
Patch Information
Nagios has addressed the issue in Nagios XI 2024R1.1.3. Apply the upgrade per the vendor guidance in the Nagios XI Security Overview. After patching, verify that directory integration endpoints no longer return bind credentials to authenticated sessions.
Workarounds
- Restrict the Nagios XI service account to the minimum directory permissions required for authentication lookups.
- Limit network access to the Nagios XI web interface to trusted administrative subnets until patching is complete.
- Disable AD/LDAP integration temporarily and fall back to local authentication if patching cannot be performed immediately.
# Verify installed Nagios XI version
cat /usr/local/nagiosxi/var/xi-version
# After upgrading, confirm version is 2024R1.1.3 or later
# and rotate the AD/LDAP bind account password in the directory
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
