CVE-2026-27307: Adobe ColdFusion DOS Vulnerability

CVE-2026-27307 Overview

CVE-2026-27307 is an Uncontrolled Resource Consumption vulnerability affecting Adobe ColdFusion versions 2023.18, 2025.6 and earlier. This vulnerability allows a high-privileged attacker to exhaust system resources, leading to application denial-of-service conditions and reduced application performance. Exploitation of this issue does not require user interaction.

Critical Impact

High-privileged attackers can exploit this vulnerability to exhaust system resources and cause denial-of-service conditions in ColdFusion applications without requiring user interaction.

Affected Products

• Adobe ColdFusion 2023 (all versions through Update 18)
• Adobe ColdFusion 2025 (all versions through Update 6)

Discovery Timeline

• 2026-04-14 - CVE CVE-2026-27307 published to NVD
• 2026-04-16 - Last updated in NVD database

Technical Details for CVE-2026-27307

Vulnerability Analysis

This vulnerability is classified as CWE-400 (Uncontrolled Resource Consumption), a class of weaknesses where an application does not properly restrict the amount of resources consumed by an actor. In the context of Adobe ColdFusion, this flaw enables attackers with high privileges to trigger excessive resource consumption within the application server.

The attack requires adjacent network access, meaning the attacker must be positioned on the same network segment or have logical adjacency to the target system. While this limits the attack surface compared to remotely exploitable vulnerabilities, organizations with compromised internal networks or shared hosting environments remain at risk.

The impact is limited to availability—there is no evidence that this vulnerability enables data exfiltration or unauthorized modifications to the system. However, successful exploitation can degrade application performance or cause complete service disruption.

Root Cause

The root cause of CVE-2026-27307 lies in improper resource management within Adobe ColdFusion. The application fails to implement adequate controls to limit resource consumption when processing certain requests or operations. This allows malicious actors with administrative or elevated privileges to submit requests that consume excessive CPU, memory, or other system resources without proper throttling or validation.

Attack Vector

The attack vector requires adjacent network access and high-level privileges within the ColdFusion environment. An attacker must first obtain elevated credentials or access rights to the ColdFusion administrative interface or application. Once authenticated with sufficient privileges, the attacker can craft requests designed to trigger resource-intensive operations that gradually or rapidly deplete available system resources.

The attack does not require any user interaction, meaning once the attacker has the necessary access, they can execute the attack autonomously. The vulnerability manifests through resource exhaustion mechanisms that overwhelm the server's capacity to handle legitimate requests, ultimately resulting in degraded performance or service unavailability.

Detection Methods for CVE-2026-27307

Indicators of Compromise

• Abnormal CPU or memory utilization spikes on ColdFusion application servers
• Unusual patterns of administrative API calls or requests from privileged accounts
• Gradual performance degradation followed by service unavailability
• Log entries showing repeated resource-intensive operations from specific privileged users

Detection Strategies

• Monitor ColdFusion application server resource utilization for anomalous consumption patterns
• Implement alerting on administrative account activity that deviates from established baselines
• Configure application performance monitoring (APM) tools to detect sudden performance degradation
• Review ColdFusion server logs for suspicious patterns of resource-intensive operations

Monitoring Recommendations

• Deploy endpoint detection and response (EDR) solutions to monitor ColdFusion server behavior
• Establish baseline resource consumption metrics and alert on significant deviations
• Implement network traffic analysis for adjacent network segments to detect unusual activity patterns
• Enable detailed audit logging for all privileged account actions within ColdFusion

How to Mitigate CVE-2026-27307

Immediate Actions Required

• Update Adobe ColdFusion 2023 to a version newer than Update 18
• Update Adobe ColdFusion 2025 to a version newer than Update 6
• Review and audit privileged account access to ColdFusion administrative functions
• Implement network segmentation to limit adjacent network attack surface

Patch Information

Adobe has released a security update addressing this vulnerability. Refer to the Adobe Security Advisory APSB26-38 for detailed patch information and download instructions. Organizations should prioritize applying the latest security updates to all affected ColdFusion installations.

Workarounds

• Restrict administrative access to ColdFusion to only essential personnel
• Implement rate limiting and request throttling at the network or application layer
• Monitor and limit resource consumption through operating system-level controls
• Isolate ColdFusion servers on dedicated network segments with strict access controls

# Example: Implement resource limits for ColdFusion JVM
# Add to ColdFusion JVM arguments to limit heap and thread usage
-Xmx2048m -Xms1024m -XX:MaxMetaspaceSize=512m
# Monitor with: jcmd <pid> VM.flags