CVE-2019-5422 in Buttle Module
Summary
by MITRE
XSS in buttle npm package version 0.2.0 causes execution of attacker-provided code in the victim's browser when an attacker creates an arbitrary file on the server.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 08/22/2023
The CVE-2019-5422 vulnerability represents a cross-site scripting flaw in the buttle npm package version 0.2.0 that enables remote code execution in victims' browsers through server-side file manipulation. This vulnerability arises from inadequate input validation and sanitization within the package's file handling mechanisms, creating a pathway for malicious actors to inject and execute arbitrary code within the context of a victim's browser session.
The technical flaw stems from the package's failure to properly sanitize user-supplied data when processing file operations on the server. When an attacker successfully creates an arbitrary file on the target server, the buttle package processes this file without adequate validation, allowing malicious content to be interpreted as executable code by the browser. This represents a classic server-side template injection vulnerability that manifests as client-side execution, leveraging the trust relationship between the browser and the web application. The vulnerability can be categorized under CWE-79 as Cross-Site Scripting, with specific implications for command execution through improper input handling.
The operational impact of this vulnerability extends beyond simple code injection, as it provides attackers with persistent access to victim browsers and potentially enables further exploitation. Once an attacker successfully exploits this vulnerability, they can execute malicious scripts that may harvest user credentials, perform unauthorized actions on behalf of users, or establish persistent backdoors. The server-side file creation aspect means that attackers can leverage legitimate file operations to introduce malicious content, making detection more challenging as the malicious activity appears to originate from legitimate system functions. This vulnerability can be mapped to ATT&CK technique T1059.007 for Command and Scripting Interpreter, specifically through web shell execution and browser-based payload delivery.
Mitigation strategies for CVE-2019-5422 should prioritize immediate package updates to versions that address the XSS vulnerability, while implementing comprehensive input validation and sanitization measures. Organizations should enforce strict file upload restrictions and implement Content Security Policy headers to limit script execution capabilities. Additionally, regular security audits of npm dependencies should be conducted to identify and remediate similar vulnerabilities in other packages. Network monitoring solutions should be configured to detect suspicious file creation patterns and anomalous behavior indicative of exploitation attempts. The vulnerability underscores the critical importance of dependency security management and the need for automated tools that can continuously scan for known vulnerabilities in software supply chains.