Attack Chain

1. An attacker identifies a vulnerable ColdFusion server running a version prior to 2023.18 or 2025.6.
2. The attacker crafts a malicious request containing a payload designed to exploit the input validation vulnerability.
3. The crafted request is sent to a ColdFusion endpoint that processes user-supplied input.
4. Due to the improper input validation, the malicious payload is processed by the ColdFusion server.
5. The payload executes arbitrary code within the context of the ColdFusion application user.
6. The attacker gains unauthorized access to the system, potentially escalating privileges.
7. The attacker can install malware, exfiltrate sensitive data, or perform other malicious activities.

Impact

Successful exploitation of this vulnerability allows an attacker to execute arbitrary code on the ColdFusion server. This can lead to complete system compromise, including data theft, malware installation, and denial of service. Given the criticality of ColdFusion in many enterprise environments, a successful attack can have significant business impact, leading to financial losses, reputational damage, and legal consequences.

Recommendation

• Apply the security patch provided by Adobe as outlined in APSB26-38 to remediate CVE-2026-27304 (reference: https://helpx.adobe.com/security/products/coldfusion/apsb26-38.html).
• Monitor web server logs for suspicious POST requests targeting ColdFusion endpoints with unusually long or malformed parameters (reference: webserver log source).
• Implement input validation rules in ColdFusion applications to prevent malicious data from being processed (reference: CWE-20).
• Deploy the Sigma rule provided below to detect potential exploitation attempts in your web server logs.