CVE-2021-43113 is a critical command injection vulnerability affecting iTextPDF in iText versions 7.0.0 to 7.1.17 (excluding 4.4.13.3). This vulnerability allows command injection via a CompareTool filename that is mishandled on the gs (Ghostscript) command line in the GhostscriptHelper.java file. With a CVSS score of 9.8, this vulnerability poses significant risk to any organization that utilizes affected versions of iTextPDF.
The critical severity of this vulnerability stems from its potential impact on confidentiality, integrity, and availability, with each aspect rated as high. Attackers exploiting this vulnerability could gain unauthorized access and execute arbitrary commands on the underlying system, leading to severe consequences for organizations.
Organizations should prioritize patching immediately to mitigate risks. As of now, there are no known public exploits or proofs of concept available, but the nature of command injection vulnerabilities suggests that they can be easily conceived by attackers.
The urgency to address this vulnerability is compounded by its classification in the Common Weakness Enumeration (CWE) as CWE-77, which deals with command injection vulnerabilities. Organizations are strongly advised to review their systems and ensure that they are not running vulnerable versions of iTextPDF.
Vulnerability Details
The official description of this vulnerability states that iTextPDF in iText 7 and up to (excluding 4.4.13.3) 7.1.17 allows command injection via a CompareTool filename that is mishandled on the gs command line in GhostscriptHelper.java. The CVSS score for this vulnerability is 9.8, which indicates a critical severity level, necessitating immediate attention from affected organizations.
Affected versions include iText 7.0.0 to 7.1.17, and the vulnerability has been assigned a CWE classification of CWE-77. The vulnerability was publicly disclosed on December 15, 2021.
Technical Analysis
The root cause of this vulnerability lies in the mishandling of input parameters in the CompareTool filename. Attackers may leverage this weakness by crafting specially designed filenames that exploit the vulnerable command line handling in GhostscriptHelper.java, leading to arbitrary command execution.
The attack vector for this vulnerability is classified as network-based, with a low attack complexity. Importantly, no privileges are required to exploit the vulnerability, and no user interaction is necessary, making it particularly dangerous.
The impacts of a successful exploitation are severe, affecting confidentiality, integrity, and availability, all rated as high. Organizations running vulnerable versions of iTextPDF should act swiftly to implement mitigations.
Risk & Impact Analysis
Risk to organizations includes potential unauthorized command execution, which could lead to data breaches, system compromise, and disruption of services. The blast radius of this vulnerability is significant, given the high likelihood of exposure in environments that utilize iTextPDF for document processing.
Organizations should assess their deployments of iTextPDF and prioritize remediation efforts based on their risk exposure. The urgency for remediation is classified as critical due to the severe impact of the vulnerability and the lack of available exploits.
Exploitation Status
Signal | Status |
|---|---|
Known Exploit | No |
Public PoC | No |
Actively Exploited | No |
Ransomware Use | No |
Affected Versions
The vulnerable versions of iTextPDF are those from 7.0.0 to 7.1.17 (excluding 4.4.13.3). Organizations should verify their installed versions and upgrade to the latest patched version to mitigate the risk associated with this vulnerability.
Mitigation & Remediation
To remediate the vulnerability, organizations should upgrade to the latest version of iTextPDF, specifically version 7.1.18 or later. If immediate patching is not feasible, organizations should implement configuration hardening to restrict command execution and monitor for unusual activity on systems running vulnerable versions.
For a thorough assessment of security posture, organizations may consider engaging in penetration testing to identify potential weaknesses in their systems.
Detection Guidance
Organizations should implement logging to detect anomalies that may indicate exploitation attempts. Specific indicators include unusual command execution patterns and logging of failed command attempts. Monitoring system changes and network traffic to the GhostscriptHelper.java component can help identify potential exploitation activities.
AppSecure Threat Intelligence Insight
The long-term significance of CVE-2021-43113 highlights the necessity for robust input validation and command handling in software development. This vulnerability represents a pattern of command injection weaknesses that can lead to severe security incidents if left unaddressed.
Security teams should learn from this incident to enhance their defensive measures against similar vulnerabilities. Regularly updating software, conducting security assessments, and following secure coding practices are essential strategies to prevent such vulnerabilities from being introduced in the first place.
For more insights into vulnerability management, organizations can explore resources such as the vulnerability management program and best practices in security testing.
To further enhance security measures, organizations can consider additional strategies such as penetration testing methodologies that are tailored to their specific environments.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
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