Adobe ColdFusion Deserialization of Untrusted Data Remote Code Execution Vulnerability (CVE-2023-26359) Security Advisory
Executive & SecOps Summary
SECOPS ASSESSMENTAdobe ColdFusion 2018 Update 15 (and earlier) and ColdFusion 2021 Update 5 (and earlier).
Successful exploitation allows unauthenticated remote attackers to execute arbitrary code in the context of the current user without any user interaction.
Immediately apply the official Adobe security patches to upgrade to ColdFusion 2018 Update 16, ColdFusion 2021 Update 6, or later.
Affected Products & Version Scope
Remediation & Live Workaround Commands
PATCH & WORKAROUND1. Official Patch & Version Upgrade Commands
Apply the official security updates provided by Adobe. You can use the ColdFusion Administrator console or execute the update via the command line as shown below:
# Navigate to the ColdFusion bin directory and run the update script (Linux example)
cd /opt/coldfusion2021/cfusion/bin
./cfupdate.sh -install
# Restart the ColdFusion service to apply changes
systemctl restart coldfusion20212. Temporary Workaround & Hardening Configuration
If patching cannot be performed immediately, restrict external access to the ColdFusion Administrator and sensitive endpoints using a reverse proxy or web application firewall (WAF).
# Nginx configuration to block external access to ColdFusion Administrator and sensitive paths
server {
listen 80;
server_name your-coldfusion-domain.com;
# Restrict access to ColdFusion Administrator Console
location ~* /(CFIDE|cfadmin|cf_scripts) {
allow 10.0.0.0/8; # Allow trusted internal network only
deny all;
}
# Forward legitimate application traffic
location ~* \.(cfc|cfm)$ {
proxy_pass http://127.0.0.1:8500;
}
}3. Log Audit & IoC Verification Commands
Verify the currently installed ColdFusion version and inspect application logs for potential deserialization exploit attempts.
# Check the installed update version in the ColdFusion directory
cat /opt/coldfusion2021/cfusion/lib/updates/chf-*.properties | grep 'update.version'
# Search for deserialization-related exceptions (e.g., ObjectInputStream errors) in the logs
grep -rn 'ObjectInputStream' /opt/coldfusion2021/cfusion/logs/exception.logBlock Exploits Instantly with Managed Virtual Patching Rules
Can't patch production immediately? Deploy managed WAF rules at the edge to intercept RCE, SQLi, and deserialization payloads before they hit your origin server.
Technical Root Cause & Exploitation Mechanics
1. Vulnerability Overview & Root Cause
This vulnerability (CVE-2023-26359) is a Deserialization of Untrusted Data vulnerability (CWE-502) residing within Adobe ColdFusion. The root cause lies in the application's failure to properly validate or sanitize serialized object data received from untrusted sources before deserializing it. This allows attackers to pass malicious serialized objects that trigger arbitrary code execution during the deserialization process.
2. Exploitation Mechanics & Attack Scenario
An attacker can exploit this vulnerability by sending a specially crafted HTTP request containing a malicious Java serialized payload to a vulnerable ColdFusion endpoint. This attack requires no authentication (pre-auth) and zero user interaction. When the ColdFusion server processes the request, the underlying Java deserialization engine reconstructs the object, triggering a gadget chain that executes arbitrary OS commands or malicious code under the privileges of the ColdFusion service.
3. Infrastructure & Business Impact
With a CVSS score of 9.8 (Critical), this vulnerability poses an extreme risk to enterprise environments. It has been added to CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming active exploitation in the wild. Successful exploitation can lead to complete system compromise, allowing attackers to establish a foothold, exfiltrate sensitive database credentials, perform lateral movement, or deploy ransomware across the internal network.
Official Vendor Advisories & References
Adobe ColdFusion versions 2018 Update 15 (and earlier) and 2021 Update 5 (and earlier) are affected by a Deserialization of Untrusted Data vulnerability that could result in arbitrary code execution in the context of the current user. Exploitation of this issue does not require user interaction.
Frequently Asked SecOps Questions (CVE-2023-26359)
FAQQ1. How critical is CVE-2023-26359 and is it actively exploited in the wild?
CVE-2023-26359 is rated CVSS 9.8 (CRITICAL) with a 30-day EPSS exploitation probability of 17.0%. It is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, requiring immediate emergency remediation.
Q2. Which vendors and products are affected by CVE-2023-26359?
Primary impacted vendors include adobe across coldfusion. Scope summary: Adobe ColdFusion 2018 Update 15 and earlier, Adobe ColdFusion 2021 Update 5 and earlier
Q3. What temporary mitigations or workarounds exist for CVE-2023-26359 before patching?
[Mitigation] Immediately apply the official Adobe security patches to upgrade to ColdFusion 2018 Update 16, ColdFusion 2021 Update 6, or later. Follow the CLI remediation commands and interactive SecOps checklist on this page to restrict exposure prior to your maintenance window.
Generate an Internal Engineering Notice or CISO Report for CVE-2023-26359
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