CVE-2017-8832 in Disk
Summary
by MITRE
Allen Disk 1.6 has XSS in the id parameter to downfile.php.
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Analysis
by VulDB Data Team • 12/06/2022
The vulnerability identified as CVE-2017-8832 affects Allen Disk version 1.6, a file sharing and management system that exposes a cross-site scripting flaw in its downfile.php script. This vulnerability specifically manifests through the id parameter, which fails to properly sanitize user input before processing and returning it to clients. The flaw represents a classic injection vulnerability that allows malicious actors to execute arbitrary JavaScript code within the context of a victim's browser session, potentially leading to unauthorized actions or data theft.
The technical implementation of this vulnerability stems from insufficient input validation and output encoding practices within the downfile.php endpoint. When the system receives an id parameter through user input, it processes this parameter without adequate sanitization measures that would prevent malicious script execution. This weakness creates an environment where attackers can craft malicious payloads that, when executed, can hijack user sessions, steal cookies, redirect users to malicious sites, or perform actions on behalf of authenticated users. The vulnerability aligns with CWE-79 which specifically addresses cross-site scripting flaws in web applications, and represents a direct violation of secure coding practices that require proper input validation and output encoding.
The operational impact of this vulnerability extends beyond simple script execution, as it can enable sophisticated attack vectors that leverage the trust relationship between the victim and the affected web application. An attacker could craft a malicious URL containing a payload that, when clicked by an authenticated user, would execute in the user's browser context. This scenario could lead to session hijacking, privilege escalation, or data exfiltration, particularly if the affected system handles sensitive user information or administrative functions. The vulnerability is particularly concerning in environments where users may inadvertently click on malicious links or where the application is used in corporate settings where user trust is paramount.
Mitigation strategies for CVE-2017-8832 should focus on implementing robust input validation and output encoding mechanisms within the affected application. The primary fix involves sanitizing all user-provided input, particularly parameters like id, through proper encoding before they are processed or returned to clients. This includes implementing context-aware output encoding that ensures any potentially malicious content is rendered harmless when displayed in web browsers. Organizations should also consider implementing content security policies to limit the execution of unauthorized scripts, and apply the principle of least privilege to restrict what actions can be performed through the vulnerable endpoint. Additionally, regular security testing including dynamic application security testing and manual code reviews should be conducted to identify similar vulnerabilities in other application components. The remediation approach should align with ATT&CK technique T1059.007 which covers scripting through web shells and malicious scripts, emphasizing the need for comprehensive protection against client-side exploitation techniques.