CVE-2017-7247 in Gazelle
Summary
by MITRE
Multiple Cross-Site Scripting (XSS) were discovered in Gazelle before 2017-03-19. The vulnerabilities exist due to insufficient filtration of user-supplied data (torrents, size) passed to the 'Gazelle-master/sections/tools/managers/multiple_freeleech.php' URL. An attacker could execute arbitrary HTML and script code in a browser in the context of the vulnerable website.
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Analysis
by VulDB Data Team • 11/15/2022
The vulnerability identified as CVE-2017-7247 represents a critical cross-site scripting flaw discovered in the Gazelle media sharing platform prior to version 2017-03-19. This vulnerability resides within the multiple_freeleech.php script located in the tools/managers section of the application's directory structure, making it a prime target for malicious actors seeking to exploit web application security weaknesses. The flaw specifically affects the application's handling of user-supplied data related to torrent information and size parameters, creating an environment where unfiltered input can be executed as malicious code within the browser context of legitimate users.
The technical implementation of this vulnerability stems from inadequate input validation and output sanitization mechanisms within the Gazelle application's codebase. When users submit torrent details or size information through the affected interface, the application fails to properly sanitize or escape these parameters before incorporating them into dynamic web page content. This insufficient filtration creates a direct pathway for attackers to inject malicious scripts that will execute in the context of other users' browsers, effectively enabling session hijacking and data exfiltration attacks. The vulnerability manifests as a classic reflected cross-site scripting issue where malicious payloads are reflected back to users through the vulnerable script's output.
The operational impact of this vulnerability extends beyond simple script execution, as it provides attackers with the capability to manipulate user sessions, steal authentication tokens, and potentially gain unauthorized access to sensitive user accounts. The attacker can craft malicious requests containing script tags that will be executed whenever other users view the affected page, leading to persistent exploitation across multiple users. This type of vulnerability particularly affects media sharing platforms where users frequently upload and share content, creating a high-risk environment for widespread exploitation. The vulnerability's presence in the tools/managers section suggests it may be accessible to users with administrative privileges, potentially enabling more severe attacks including privilege escalation.
Mitigation strategies for CVE-2017-7247 should focus on implementing robust input validation and output encoding mechanisms throughout the application's codebase. The most effective approach involves sanitizing all user-supplied input through proper escaping techniques before incorporating it into dynamic web content, with the specific implementation following established security guidelines such as those outlined in the OWASP Top Ten project. Additionally, implementing a Content Security Policy (CSP) header can provide an additional layer of protection by restricting the sources from which scripts can be executed within the application context. The vulnerability aligns with CWE-79 which specifically addresses cross-site scripting flaws, and its exploitation patterns correspond to techniques described in the MITRE ATT&CK framework under the web application attack category, particularly focusing on code injection and session management compromise tactics that target the application's input handling mechanisms.