CVE-2026-24414: Icinga PowerShell Information Disclosure

CVE-2026-24414 Overview

CVE-2026-24414 is an Insecure Permissions vulnerability affecting the Icinga PowerShell Framework, a configuration and monitoring solution for Windows environments. The vulnerability stems from overly permissive access controls on the certificate directory, allowing any local user to read the private key of the Icinga certificate for the affected host. This exposure of cryptographic material could enable attackers with local access to impersonate the Icinga agent, intercept encrypted communications, or perform other malicious actions that compromise the integrity of the monitoring infrastructure.

Critical Impact

Local users can read the Icinga certificate private key, potentially enabling certificate theft, service impersonation, and compromise of encrypted monitoring communications across the Windows environment.

Affected Products

• Icinga PowerShell Framework versions prior to 1.13.4
• Icinga PowerShell Framework versions prior to 1.12.4
• Icinga PowerShell Framework versions prior to 1.11.2

Discovery Timeline

• 2026-01-29 - CVE CVE-2026-24414 published to NVD
• 2026-01-29 - Last updated in NVD database

Technical Details for CVE-2026-24414

Vulnerability Analysis

This vulnerability is classified under CWE-276 (Incorrect Default Permissions), indicating that the Icinga PowerShell Framework was deployed with default permissions that are more permissive than necessary. The certificate directory at C:\Program Files\WindowsPowerShell\modules\icinga-powershell-framework\certificate is configured to grant read access to all users on the system. This design flaw exposes the private key material used by the Icinga agent for secure communications.

The local attack vector means an attacker requires existing access to the target system, but once obtained, no special privileges are needed beyond standard user permissions. The vulnerability affects the confidentiality of the cryptographic assets without directly impacting integrity or availability. However, the stolen private key could be leveraged for secondary attacks that do affect those security properties.

Root Cause

The root cause is an improper configuration of Access Control Lists (ACLs) on the certificate directory during installation or framework setup. The Icinga PowerShell Framework fails to restrict read permissions on the certificate folder to only the Icinga service account and administrators. Instead, the default permissions allow all authenticated users to traverse and read the contents of this sensitive directory, including private key files that should be protected with strict access controls.

Attack Vector

An attacker with local access to a Windows system running the vulnerable Icinga PowerShell Framework can exploit this vulnerability through the following attack path:

1. Authenticate to the target Windows system with any valid user account
2. Navigate to the certificate directory at C:\Program Files\WindowsPowerShell\modules\icinga-powershell-framework\certificate
3. Read the private key file stored within the directory
4. Use the extracted private key to impersonate the Icinga agent, decrypt captured traffic, or perform other attacks against the monitoring infrastructure

The vulnerability also affects the Icinga 2 agent installation at C:\ProgramData\icinga2\var, which contains similar permission issues tracked separately as CVE-2026-24413.

Detection Methods for CVE-2026-24414

Indicators of Compromise

• Unexpected file access events on the C:\Program Files\WindowsPowerShell\modules\icinga-powershell-framework\certificate directory by non-administrative users
• Audit logs showing read operations on certificate private key files by unauthorized accounts
• Evidence of certificate files being copied or exported from the Icinga certificate directory
• Unusual authentication attempts using the Icinga agent certificate from unexpected sources

Detection Strategies

• Enable Windows Security Auditing for object access on the Icinga certificate directories to log all read attempts
• Monitor for file read operations targeting .pem, .key, or certificate-related files within the Icinga framework paths
• Implement endpoint detection rules to alert on non-service accounts accessing the certificate directory
• Review current ACL configurations using PowerShell Get-Acl cmdlet to identify overly permissive settings

Monitoring Recommendations

• Configure SentinelOne to monitor file access patterns on sensitive Icinga directories
• Set up alerts for any process other than the Icinga service reading from the certificate folder
• Establish baseline access patterns and alert on deviations indicating potential reconnaissance or exfiltration
• Correlate certificate directory access events with user authentication events to identify suspicious local activity

How to Mitigate CVE-2026-24414

Immediate Actions Required

• Upgrade the Icinga PowerShell Framework to patched versions: 1.13.4, 1.12.4, or 1.11.2
• Apply manual ACL restrictions to the certificate directory if immediate patching is not possible
• Audit systems to identify all installations of vulnerable Icinga PowerShell Framework versions
• Review certificate usage logs to determine if private keys may have been accessed by unauthorized users

Patch Information

Icinga has released security patches addressing this vulnerability in versions 1.13.4, 1.12.4, and 1.11.2 of the Icinga PowerShell Framework. Upgrading to any of these versions will automatically correct the insecure permissions on the certificate directory. Additionally, the upgrade process will also remediate the related vulnerability CVE-2026-24413 affecting the Icinga 2 agent. For detailed patch information, refer to the Icinga Blog Release Announcement and the GitHub Security Advisory for Icinga PowerShell Framework.

Workarounds

• Manually restrict ACL permissions on C:\Program Files\WindowsPowerShell\modules\icinga-powershell-framework\certificate to allow access only for the Icinga service user and administrators
• Apply the same ACL restrictions to C:\ProgramData\icinga2\var to address the related Icinga 2 agent issue
• Remove inherited permissions and explicitly set restrictive ACLs on all subdirectories and files within the certificate path
• Consider regenerating certificates after applying fixes if there is suspicion of prior unauthorized access

# Manual ACL remediation for Icinga certificate directory
$certPath = "C:\Program Files\WindowsPowerShell\modules\icinga-powershell-framework\certificate"
$acl = Get-Acl $certPath
$acl.SetAccessRuleProtection($true, $false)
$adminRule = New-Object System.Security.AccessControl.FileSystemAccessRule("BUILTIN\Administrators", "FullControl", "ContainerInherit,ObjectInherit", "None", "Allow")
$systemRule = New-Object System.Security.AccessControl.FileSystemAccessRule("NT AUTHORITY\SYSTEM", "FullControl", "ContainerInherit,ObjectInherit", "None", "Allow")
$acl.AddAccessRule($adminRule)
$acl.AddAccessRule($systemRule)
Set-Acl $certPath $acl