CVE-2015-2522 in SharePoint Foundation
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in Microsoft SharePoint Foundation 2013 SP1 allows remote authenticated users to inject arbitrary web script or HTML via crafted content, aka "Microsoft SharePoint XSS Spoofing Vulnerability."
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 06/14/2022
The vulnerability identified as CVE-2015-2522 represents a critical cross-site scripting flaw within Microsoft SharePoint Foundation 2013 SP1 that enables remote authenticated attackers to execute malicious web scripts or HTML content through crafted input. This vulnerability falls under the Common Weakness Enumeration category CWE-79, which specifically addresses improper neutralization of input during web page generation, making it a classic example of a server-side XSS vulnerability. The flaw exists in the SharePoint Foundation's content handling mechanisms where user-supplied data is not adequately sanitized before being rendered in web pages, creating an attack surface that can be exploited by malicious actors who have already gained authentication credentials.
The technical exploitation of this vulnerability occurs when authenticated users interact with SharePoint Foundation 2013 SP1 and encounter content that has been manipulated by an attacker. The malicious content can be injected through various SharePoint features including but not limited to document libraries, lists, web parts, and user profile information. When the vulnerable SharePoint instance processes and renders this malicious content, the embedded scripts execute within the context of the victim's browser session, potentially allowing attackers to steal session cookies, perform unauthorized actions, or redirect users to malicious websites. This particular vulnerability is classified as an XSS spoofing vulnerability because it specifically targets the rendering of content in a way that can deceive users into believing they are interacting with legitimate SharePoint functionality while actually executing attacker-controlled code.
The operational impact of CVE-2015-2522 extends beyond simple script execution, as it can enable more sophisticated attacks within the SharePoint environment. Attackers can leverage this vulnerability to establish persistent access through session hijacking, escalate privileges within the SharePoint context, or use the compromised system as a launching point for broader attacks against the organization's network infrastructure. The vulnerability particularly affects organizations that rely heavily on SharePoint for collaboration and document management, as the attack vector requires only authenticated access, which is often readily available through legitimate user accounts. From an ATT&CK framework perspective, this vulnerability maps to techniques such as T1059.007 (Command and Scripting Interpreter: PowerShell) and T1566 (Phishing) as attackers can use the XSS to deliver malicious payloads or manipulate user behavior. The impact is amplified in environments where SharePoint serves as a central hub for business-critical applications and data, potentially leading to data breaches, intellectual property theft, or service disruption.
Organizations should implement multiple layers of defense to mitigate the risks associated with CVE-2015-2522. The primary mitigation strategy involves applying Microsoft's security patches and updates as soon as they become available, which typically address the root cause by implementing proper input sanitization and output encoding mechanisms. Additionally, organizations should enforce strict content validation policies, implement robust web application firewalls, and utilize security monitoring tools that can detect anomalous content injection patterns. Regular security assessments and user awareness training are also crucial components of a comprehensive defense strategy, as they help identify potential exploitation attempts and educate users about recognizing suspicious SharePoint content. The vulnerability underscores the importance of maintaining up-to-date security practices and demonstrates how even authenticated access can be exploited to compromise system integrity, making it essential for organizations to maintain continuous vigilance and proactive security measures.