CVE-2026-27308: Adobe ColdFusion DoS Vulnerability

CVE-2026-27308 Overview

CVE-2026-27308 is an Uncontrolled Resource Consumption vulnerability affecting Adobe ColdFusion versions 2023.18, 2025.6 and earlier. This vulnerability enables a high-privileged attacker to exhaust system resources, leading to application denial-of-service conditions and degraded application performance. The vulnerability can be exploited without user interaction, though it requires adjacent network access and elevated privileges.

Critical Impact

Exploitation of this vulnerability can result in resource exhaustion causing application slowdowns and potential denial-of-service, impacting availability of ColdFusion-powered applications and services.

Affected Products

• Adobe ColdFusion 2023 (all versions through Update 18)
• Adobe ColdFusion 2025 (all versions through Update 6)
• All intermediate updates for both product lines

Discovery Timeline

• April 14, 2026 - CVE-2026-27308 published to NVD
• April 16, 2026 - Last updated in NVD database

Technical Details for CVE-2026-27308

Vulnerability Analysis

This vulnerability is classified as CWE-400 (Uncontrolled Resource Consumption), a weakness where the application fails to properly limit the allocation of resources requested by external actors. In the context of Adobe ColdFusion, an authenticated attacker with high privileges can trigger resource exhaustion conditions that consume excessive CPU, memory, or other system resources.

The attack requires adjacent network access, meaning the attacker must be on the same network segment or have logical adjacency to the target system. While the privilege requirements are high, mitigating the immediate risk, organizations should still address this vulnerability as privileged attackers or compromised administrative accounts could leverage it to disrupt business operations.

Root Cause

The vulnerability stems from inadequate resource management within Adobe ColdFusion's request handling mechanisms. The application fails to implement proper controls to limit resource allocation when processing certain operations, allowing a high-privileged user to submit requests that consume disproportionate system resources. This lack of throttling or resource limits enables the exhaustion attack vector.

Attack Vector

The attack requires an authenticated session with high-level privileges on an adjacent network. The attacker can submit malicious requests designed to consume excessive resources without any user interaction required. The exploitation flow involves sending specially crafted requests that trigger resource-intensive operations within ColdFusion, gradually or rapidly exhausting available system resources.

Due to the nature of resource consumption attacks, the impact is primarily to availability, with no direct effect on confidentiality or integrity of data. The attacker cannot use this vulnerability to access or modify sensitive information but can effectively render the application unresponsive.

Detection Methods for CVE-2026-27308

Indicators of Compromise

• Unusual spikes in CPU or memory utilization on ColdFusion servers without corresponding increases in legitimate traffic
• Degraded application response times or timeout errors reported by users
• ColdFusion application logs showing repeated resource-intensive operations from privileged accounts
• System logs indicating out-of-memory conditions or process crashes related to ColdFusion services

Detection Strategies

• Monitor ColdFusion server resource utilization patterns and establish baselines to detect anomalous consumption
• Implement logging and alerting for administrative actions within ColdFusion that trigger resource-intensive operations
• Deploy network monitoring to identify unusual traffic patterns from adjacent network segments targeting ColdFusion instances
• Review authentication logs for suspicious privileged account activity or potential account compromise indicators

Monitoring Recommendations

• Configure system monitoring to alert when ColdFusion processes exceed resource consumption thresholds
• Implement centralized logging for all ColdFusion administrative activities with real-time analysis capabilities
• Deploy application performance monitoring (APM) solutions to track ColdFusion response times and resource usage trends
• Regularly audit privileged account access and review logs for signs of misuse

How to Mitigate CVE-2026-27308

Immediate Actions Required

• Apply the latest security updates from Adobe for ColdFusion 2023 and 2025 versions as outlined in APSB26-38
• Review and restrict high-privilege account access to only essential personnel
• Implement network segmentation to limit adjacent network exposure to ColdFusion servers
• Configure resource limits and rate limiting where possible within ColdFusion server settings

Patch Information

Adobe has released security patches addressing this vulnerability. Refer to the Adobe ColdFusion Security Bulletin (APSB26-38) for complete patch information and update instructions. Organizations should update to the latest available versions:

• ColdFusion 2023: Update to a version newer than Update 18
• ColdFusion 2025: Update to a version newer than Update 6

Workarounds

• Restrict network access to ColdFusion administrative interfaces to trusted management networks only
• Implement strict access controls and multi-factor authentication for privileged ColdFusion accounts
• Deploy web application firewalls (WAF) or reverse proxies with rate limiting capabilities to mitigate resource exhaustion attempts
• Configure operating system-level resource limits (cgroups, ulimits) to constrain ColdFusion process resource consumption

# Example: Restrict ColdFusion admin access by IP using firewall rules
# Replace with your trusted management network CIDR
iptables -A INPUT -p tcp --dport 8500 -s 10.0.10.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 8500 -j DROP