CVE-2014-4663 in WordThumb
Summary
by MITRE
TimThumb 2.8.13 and WordThumb 1.07, when Webshot (aka Webshots) is enabled, allows remote attackers to execute arbitrary commands via shell metacharacters in the src parameter.
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Analysis
by VulDB Data Team • 02/23/2025
The vulnerability identified as CVE-2014-4663 represents a critical command injection flaw affecting TimThumb 2.8.13 and WordThumb 1.07 content management systems. This security weakness manifests when the Webshot feature is enabled, creating an attack surface where remote adversaries can manipulate the src parameter to inject malicious shell commands. The vulnerability stems from inadequate input validation and sanitization mechanisms within the image processing components of these applications, allowing attackers to bypass normal execution flows and directly interact with the underlying operating system through the web server interface.
The technical exploitation of this vulnerability occurs through the manipulation of the src parameter in the Webshot functionality, which processes external image sources for thumbnail generation. When shell metacharacters such as semicolons, ampersands, or backticks are injected into this parameter, the system fails to properly sanitize the input before passing it to shell execution functions. This creates a direct pathway for arbitrary code execution, enabling attackers to perform operations ranging from simple file reads to complete system compromise. The vulnerability maps directly to CWE-77 which describes improper neutralization of special elements used in a command, and aligns with ATT&CK technique T1059.001 for command and script injection. The flaw essentially allows attackers to execute commands with the privileges of the web server process, potentially leading to unauthorized access to sensitive data, system file manipulation, and further network reconnaissance.
The operational impact of this vulnerability extends beyond immediate code execution capabilities to encompass broader security implications for affected web environments. Organizations utilizing vulnerable versions of TimThumb or WordThumb face significant risks including data breaches, unauthorized system access, and potential lateral movement within their network infrastructure. The remote nature of the attack means that adversaries can exploit this vulnerability from anywhere on the internet without requiring local access or credentials, making it particularly dangerous for public-facing web applications. The vulnerability affects not only the immediate application but can also compromise the entire hosting environment, as successful exploitation typically grants attackers the ability to read system files, establish persistent backdoors, and potentially escalate privileges to gain administrative control over the server.
Mitigation strategies for CVE-2014-4663 should prioritize immediate patching of affected applications to the latest versions that contain proper input validation and sanitization routines. System administrators must disable the Webshot functionality when not required, as this reduces the attack surface significantly. Network-level protections including web application firewalls and input filtering rules can provide additional defense in depth measures, though these should complement rather than replace proper application patches. Security monitoring should focus on detecting unusual command execution patterns and unauthorized file access attempts, particularly around the vulnerable image processing endpoints. Regular security assessments and vulnerability scanning should be conducted to identify similar flaws in other web applications and components, as this vulnerability demonstrates the importance of proper input validation in image processing and content management systems. Organizations should also implement principle of least privilege configurations for web server processes to limit the potential impact of successful exploitation, ensuring that compromised applications cannot access sensitive system resources beyond their intended functionality.