CVE-2014-0114

What it actually does

The vulnerability allows remote attackers to manipulate the ClassLoader by supplying a class parameter that bypasses suppression of the class property in Apache Commons BeanUtils, enabling arbitrary code execution through deserialization and reflection abuse.

Why it matters to the business

Successful exploitation can lead to full server compromise, data breaches, and service disruption on unpatched systems; the high EPSS score and weaponized exploit maturity indicate elevated risk of automated attacks even years after disclosure.

How an attack unfolds

An attacker sends crafted HTTP requests containing a malicious class parameter to an affected Struts application, which invokes getClass on the ActionForm and loads attacker-controlled classes via the manipulated ClassLoader, achieving remote code execution without authentication.

How to fix it

Upgrade to fixed package versions such as linux-azure 4.15.0-1023.24~14.04.1 on Ubuntu 14.04 LTS; for Struts applications, migrate away from Struts 1.x or apply patches that suppress the class property in BeanUtils 1.9.2 or later.

How to confirm the fix worked

Verify package versions match or exceed the fixed releases listed for each distribution; test affected endpoints with benign class parameter inputs to confirm rejection; review application dependency trees to ensure no vulnerable commons-beanutils JARs remain.

Typical attack path

1. Identify publicly exposed Struts 1.x endpoints or applications using vulnerable BeanUtils versions
2. Craft and send HTTP requests with a manipulated class parameter targeting ActionForm objects
3. Trigger ClassLoader manipulation to load and execute arbitrary attacker-supplied classes
4. Establish persistence or exfiltrate data after achieving code execution

How to detect it

Review web server and application logs for requests containing class parameters passed to ActionForm or similar objects; search for process executions or file writes indicative of unexpected ClassLoader activity; correlate with historical access logs around the time of known weaponized exploit availability.

• class=.*ActionForm
• getClass.*class parameter
• manipulated ClassLoader in Struts request logs

What your security team should do

• Immediately apply the specified fixed package versions on all affected Ubuntu systems
• Scan application inventories for any remaining Struts 1.x or BeanUtils <=1.9.1 usage
• Implement WAF rules to block requests containing suspicious class parameters
• Monitor EPSS trends and exploit maturity indicators for similar legacy components