CVE-2017-8304 in FTA
Summary
by MITRE
An issue was discovered on Accellion FTA devices before FTA_9_12_180. courier/1000@/oauth/playground/callback.html allows XSS with a crafted URI.
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Analysis
by VulDB Data Team • 09/24/2020
The vulnerability identified as CVE-2017-8304 affects Accellion FTA (File Transfer Appliance) devices running versions prior to FTA_9_12_180. This security flaw resides within the courier/1000@/oauth/playground/callback.html component of the system, representing a significant cross-site scripting vulnerability that could be exploited by malicious actors to compromise user sessions and execute unauthorized actions. The issue stems from insufficient input validation and output encoding mechanisms within the web interface, specifically in how the system handles URI parameters passed to the oauth callback endpoint.
The technical implementation of this vulnerability allows an attacker to craft malicious URIs that contain script payloads which are then executed within the context of a victim's browser session. When a user visits a specially crafted link containing malicious JavaScript code within the URI parameters, the vulnerable application fails to properly sanitize or encode these inputs before rendering them in the web page response. This creates an environment where the malicious script code gets executed in the victim's browser, potentially leading to session hijacking, data theft, or unauthorized administrative actions. The vulnerability specifically affects the OAuth playground callback functionality, which is designed for testing authentication flows but becomes a vector for exploitation when proper security controls are absent.
The operational impact of this vulnerability is substantial as it enables attackers to perform unauthorized actions on behalf of legitimate users within the Accellion FTA environment. An attacker could potentially steal user sessions, access sensitive files, modify system configurations, or escalate privileges within the appliance. The vulnerability is particularly concerning because it affects the authentication and authorization mechanisms of the system, which are fundamental to maintaining security boundaries. The XSS payload could be used to capture authentication tokens, redirect users to malicious sites, or perform actions that appear to originate from legitimate users within the system. This could lead to complete compromise of the file transfer appliance and potentially broader network access if the appliance is integrated with other systems.
Organizations should immediately implement mitigations including updating to the patched version FTA_9_12_180 or later, which addresses the input validation issues in the affected component. Network segmentation and web application firewalls can provide additional layers of protection by monitoring and blocking suspicious URI patterns. The vulnerability aligns with CWE-79 Cross-site Scripting and follows the ATT&CK technique T1059.007 Command and Scripting Interpreter: JavaScript, where attackers leverage browser-based scripting to execute malicious code. Security teams should also implement regular security assessments of web applications and conduct thorough input validation testing to identify similar vulnerabilities in other components of the system. The incident underscores the importance of proper output encoding and input sanitization practices in web applications, particularly in authentication and authorization pathways where the consequences of exploitation can be severe.