CVE-2015-7491 in WebSphere Portal
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in IBM WebSphere Portal 8.0.x before 8.0.0.1 CF20 and 8.5.x before 8.5.0.0 CF09 allows remote authenticated users to inject arbitrary web script or HTML via a crafted URL.
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Analysis
by VulDB Data Team • 02/01/2019
The vulnerability identified as CVE-2015-7491 represents a critical cross-site scripting flaw within IBM WebSphere Portal versions 8.0.x prior to 8.0.0.1 CF20 and 8.5.x prior to 8.5.0.0 CF09. This security weakness resides in the portal's handling of user-supplied input within URL parameters, creating an avenue for malicious actors to execute arbitrary web scripts or HTML code within the context of authenticated user sessions. The vulnerability specifically affects the portal's web application framework where it fails to properly sanitize or validate URL components before processing them, allowing attackers to craft malicious URLs that bypass standard input validation mechanisms.
The technical exploitation of this XSS vulnerability occurs through the manipulation of URL parameters that are subsequently processed by the WebSphere Portal server. When authenticated users navigate to a crafted URL containing malicious script payloads, the portal's insufficient input validation allows the injected content to be executed within the victim's browser session. This behavior aligns with CWE-79, which classifies cross-site scripting vulnerabilities as weaknesses that allow attackers to inject malicious scripts into web applications viewed by other users. The vulnerability's impact is amplified by the fact that it requires only authentication, meaning that attackers can leverage existing user sessions rather than needing to perform additional authentication attempts.
From an operational perspective, this vulnerability poses significant risks to organizations utilizing IBM WebSphere Portal as their primary enterprise portal solution. The remote authenticated nature of the attack means that malicious actors can exploit this weakness from any network location without requiring physical access to the system. Successful exploitation could lead to session hijacking, credential theft, data exfiltration, and the potential for privilege escalation within the portal environment. Attackers could leverage this vulnerability to impersonate legitimate users, access restricted content, modify portal configurations, or redirect users to malicious websites. The attack vector specifically targets URL parameters, making it particularly challenging to detect and prevent since legitimate portal functionality often relies on parameterized URLs.
The mitigation strategies for CVE-2015-7491 primarily focus on applying the vendor-provided security fixes and patches. Organizations should immediately upgrade their WebSphere Portal installations to the affected versions mentioned in the advisory, specifically moving beyond 8.0.0.1 CF20 for the 8.0.x series and 8.5.0.0 CF09 for the 8.5.x series. Additionally, implementing proper input validation and output encoding mechanisms can serve as defensive measures, though these should not be considered replacements for official patches. Organizations should also consider implementing web application firewalls that can detect and block suspicious URL patterns, and establish monitoring procedures to identify unusual traffic patterns that may indicate exploitation attempts. The vulnerability's classification under ATT&CK technique T1059.008, which covers script injection, highlights the importance of comprehensive application security controls that address multiple attack vectors and maintain defense in depth principles throughout the application lifecycle.