CVE-2025-34074: Lucee Administrative Interface RCE Flaw

CVE-2025-34074 Overview

An authenticated remote code execution vulnerability exists in Lucee's administrative interface due to an insecure design flaw in the scheduled task functionality. This vulnerability allows an attacker with administrative access to configure a scheduled job that retrieves a malicious .cfm file from an attacker-controlled server, writes it to the Lucee webroot, and executes it with the privileges of the Lucee service account. The lack of integrity checks, path restrictions, or execution controls for scheduled task fetches makes this feature susceptible to abuse for arbitrary code execution.

Critical Impact

Authenticated attackers can achieve full remote code execution on systems running Lucee by exploiting the scheduled task feature to deploy and execute malicious ColdFusion Markup (CFM) files.

Affected Products

• Lucee CFML Engine (versions with vulnerable scheduled task functionality)
• Lucee Administrative Web Interface (/lucee/admin/web.cfm)

Discovery Timeline

• 2025-07-02 - CVE-2025-34074 published to NVD
• 2025-07-03 - Last updated in NVD database

Technical Details for CVE-2025-34074

Vulnerability Analysis

This vulnerability stems from a design weakness in how Lucee handles scheduled tasks within its administrative interface (CWE-94: Code Injection). The scheduled task feature is intended to allow administrators to automate recurring operations, including fetching remote resources. However, the implementation fails to enforce critical security controls that would prevent abuse.

When an administrator configures a scheduled job to fetch a remote file, Lucee does not validate the source, verify the integrity of the retrieved content, restrict the destination path, or prevent execution of fetched files. This allows an attacker who has compromised or obtained administrative credentials to weaponize this legitimate feature for malicious purposes.

The attack requires authenticated access to the Lucee administrative panel, but once that access is obtained, exploitation is straightforward. A Metasploit module already exists for this vulnerability, indicating that exploitation is well-documented and accessible to attackers with moderate skill levels.

Root Cause

The root cause is the absence of security controls in Lucee's scheduled task implementation. Specifically:

1. No Source Validation: Lucee accepts URLs from any external server without verification
2. No Integrity Checks: Retrieved files are not validated against checksums or signatures
3. No Path Restrictions: Files can be written directly to the webroot directory
4. No Execution Prevention: Downloaded .cfm files are immediately executable by the Lucee engine

This represents a classic "insecure by design" pattern where powerful administrative functionality lacks appropriate safeguards.

Attack Vector

The attack is network-based and requires authenticated access to the Lucee administrative interface. The exploitation workflow involves:

1. Initial Access: Attacker gains credentials to /lucee/admin/web.cfm through credential theft, brute force, or default credentials
2. Malicious Server Setup: Attacker hosts a malicious .cfm payload on an attacker-controlled web server
3. Scheduled Task Creation: Attacker creates a scheduled job configured to fetch the remote payload and save it to the Lucee webroot
4. Task Execution: The scheduled task runs (either immediately or on schedule), downloading the malicious file
5. Payload Execution: Attacker requests the downloaded .cfm file via HTTP, triggering code execution with Lucee service account privileges

The vulnerability is network-exploitable with no user interaction required beyond the initial authentication, enabling attackers to establish persistent access or pivot to other systems on the network.

Detection Methods for CVE-2025-34074

Indicators of Compromise

• Unexpected .cfm files appearing in the Lucee webroot directory
• Scheduled tasks configured to fetch files from external or unknown URLs
• HTTP requests to newly created .cfm files from external IP addresses
• Lucee service account executing suspicious commands or spawning unexpected child processes
• Network connections from the Lucee server to unusual external hosts

Detection Strategies

• Monitor Lucee administrative interface access logs for scheduled task creation or modification events
• Implement file integrity monitoring on the Lucee webroot directory to detect unauthorized file additions
• Deploy network monitoring to identify outbound connections from the Lucee server to unknown external hosts
• Alert on the creation of new scheduled tasks, especially those targeting external URLs

Monitoring Recommendations

• Enable verbose logging for the Lucee administrative interface and scheduled task subsystem
• Configure SIEM rules to correlate administrative logins with subsequent scheduled task changes
• Monitor for web shell indicators such as command execution functions in newly created files
• Implement egress filtering to restrict which external hosts the Lucee server can communicate with

How to Mitigate CVE-2025-34074

Immediate Actions Required

• Audit all existing scheduled tasks in Lucee for suspicious remote URL configurations
• Review administrative account credentials and enforce strong, unique passwords
• Restrict network access to the Lucee administrative interface (/lucee/admin/) to trusted management networks only
• Implement multi-factor authentication for administrative access where possible
• Consider disabling the scheduled task feature entirely if not required for business operations

Patch Information

Consult the Lucee GitHub repository for the latest security updates and patches addressing this vulnerability. Review the VulnCheck Advisory for Lucee RCE for specific remediation guidance. Note that this issue is distinct from CVE-2024-55354 and may require separate patching.

Workarounds

• Restrict access to /lucee/admin/ endpoints at the web server or load balancer level using IP allowlists
• Implement egress filtering on the Lucee server to block outbound HTTP/HTTPS connections to unauthorized destinations
• Deploy a web application firewall (WAF) to monitor and block suspicious administrative actions
• Run Lucee with a low-privilege service account to limit the impact of successful exploitation
• Consider placing the administrative interface on a separate, isolated network segment