CVE-2022-25847 in serve-lite
Summary
by MITRE • 01/26/2023
All versions of the package serve-lite are vulnerable to Cross-site Scripting (XSS) because when it detects a request to a directory, it renders a file listing of all of its contents with links that include the actual file names without any sanitization or output encoding.
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Analysis
by VulDB Data Team • 04/01/2025
The vulnerability identified as CVE-2022-25847 affects the serve-lite package, a lightweight static file server commonly used in development environments and testing scenarios. This cross-site scripting vulnerability stems from inadequate input validation and output encoding mechanisms within the package's directory listing functionality. When the serve-lite package processes requests to directories, it automatically generates file listings that display all contents with hyperlinks pointing to individual files. The flaw occurs because the package fails to sanitize or encode the actual file names before incorporating them into the HTML output, creating an environment where malicious actors can inject arbitrary script code through specially crafted file names.
This vulnerability falls under the CWE-79 category of Cross-Site Scripting, specifically representing a reflected XSS attack vector where user-supplied data is directly embedded into web responses without proper sanitization. The ATT&CK framework categorizes this under T1203 - Exploitation for Client Execution, as the vulnerability enables attackers to execute malicious scripts in the context of a victim's browser session. The impact extends beyond simple script injection, as successful exploitation could allow attackers to steal session cookies, perform unauthorized actions on behalf of users, or redirect victims to malicious websites. The vulnerability is particularly concerning in development environments where multiple users may have access to the same server instance, as it provides a potential entry point for privilege escalation attacks.
The operational impact of CVE-2022-25847 is significant for organizations using serve-lite in their development workflows, continuous integration pipelines, or testing environments. Attackers can exploit this vulnerability by creating file names containing malicious script payloads that will execute when users browse directory listings. The vulnerability affects all versions of the package, indicating a fundamental design flaw that requires immediate remediation. In production environments, this vulnerability could lead to data breaches, session hijacking, and potential lateral movement within networks where developers have access to sensitive resources. The vulnerability is particularly dangerous in collaborative development environments where developers may inadvertently click on maliciously crafted file names or where automated tools may traverse directory structures containing compromised files.
Mitigation strategies for CVE-2022-25847 should prioritize immediate package updates to versions that have addressed the XSS vulnerability through proper input sanitization and output encoding. Organizations should implement comprehensive security reviews of their development toolchains to identify all instances where serve-lite or similar packages are in use. The remediation process should include validating that file names are properly encoded before inclusion in HTML output, implementing Content Security Policy headers to limit script execution, and conducting regular security audits of development environments. Additionally, developers should be trained to recognize the risks associated with directory listing functionality and to avoid using vulnerable packages in production environments where user input might be processed. The vulnerability serves as a reminder of the importance of input validation and output encoding practices in web applications, aligning with security best practices outlined in OWASP Top Ten and NIST cybersecurity guidelines for preventing cross-site scripting attacks.