CVE-2015-4656 in Photo Station
Summary
by MITRE
Multiple cross-site scripting (XSS) vulnerabilities in Synology Photo Station before 6.3-2945 allow remote attackers to inject arbitrary web script or HTML via the (1) success parameter to login.php or (2) crafted URL parameters to index.php, as demonstrated by the t parameter to photo/.
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Analysis
by VulDB Data Team • 04/10/2019
The vulnerability CVE-2015-4656 represents a critical cross-site scripting flaw in Synology Photo Station versions prior to 6.3-2945, exposing users to significant security risks through web script injection attacks. This vulnerability resides in the application's handling of user-supplied input parameters within the login and photo viewing functionalities, creating pathways for malicious actors to execute arbitrary code within the context of victim sessions. The flaw manifests through two distinct attack vectors that leverage different parameter names and endpoints within the application's web interface.
The technical implementation of this vulnerability stems from inadequate input validation and output encoding mechanisms within the Synology Photo Station application. Attackers can exploit the first vector by manipulating the success parameter in the login.php endpoint, while the second vector targets crafted URL parameters in index.php, specifically the t parameter within the photo/ directory. These attack vectors demonstrate a classic XSS vulnerability pattern where user-controllable input is directly reflected back to the browser without proper sanitization or encoding. The vulnerability aligns with CWE-79, which specifically addresses Cross-Site Scripting flaws, and represents a weakness in input validation that allows malicious payloads to be executed in the victim's browser context.
The operational impact of this vulnerability extends beyond simple script injection, as it enables attackers to perform session hijacking, steal user credentials, and potentially escalate privileges within the application. When victims navigate to maliciously crafted URLs containing the XSS payload, the injected scripts execute within their browser sessions, potentially allowing attackers to access the victim's photo library, modify content, or perform unauthorized actions. This vulnerability particularly affects organizations relying on Synology Photo Station for digital asset management, as it creates opportunities for unauthorized access to sensitive visual content and user data. The attack requires minimal technical expertise and can be executed through social engineering techniques, making it particularly dangerous in enterprise environments where users may inadvertently click on malicious links.
Mitigation strategies for this vulnerability should include immediate application updates to Synology Photo Station version 6.3-2945 or later, which contain the necessary patches to address the input validation flaws. Organizations should also implement comprehensive web application firewalls that can detect and block malicious XSS payloads, while establishing strict input validation policies for all user-supplied parameters. Network administrators should monitor for suspicious traffic patterns and implement security awareness training for users to recognize potentially malicious links. Additionally, the principle of least privilege should be enforced by limiting the permissions of Photo Station users and implementing proper access controls to minimize the potential impact of successful exploitation. The vulnerability demonstrates the importance of regular security updates and proper input sanitization practices, aligning with ATT&CK technique T1059.007 for scripting and T1566.001 for spearphishing via web links in adversarial security contexts.