CVE-2015-4297 in WebEx Node for Media Convergence Server
Summary
by MITRE
Open redirect vulnerability in Cisco WebEx Node for Media Convergence Server (MCS) allows remote attackers to redirect users to arbitrary web sites and conduct phishing attacks via crafted HTTP request parameters, aka Bug ID CSCuv32136.
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Analysis
by VulDB Data Team • 10/18/2017
The CVE-2015-4297 vulnerability represents a critical open redirect flaw discovered in Cisco WebEx Node for Media Convergence Server (MCS) software. This vulnerability resides within the web interface of the Media Convergence Server, which serves as a core component in Cisco's WebEx collaboration platform. The flaw allows remote attackers to manipulate HTTP request parameters in a way that causes the application to redirect users to arbitrary web addresses without proper validation of the destination URLs. The vulnerability was officially documented under Bug ID CSCuv32136 and affects specific versions of the Cisco WebEx MCS software, particularly those deployed in enterprise environments where collaboration and video conferencing services are utilized.
The technical implementation of this vulnerability stems from inadequate input validation within the WebEx MCS web application. When processing HTTP requests containing redirect parameters, the system fails to properly sanitize or validate the destination URLs provided by users. This allows attackers to craft malicious HTTP requests with crafted parameter values that specify alternative URLs for redirection. The flaw operates at the application layer and can be exploited through web-based attack vectors, making it particularly dangerous as it requires no special privileges or access to the internal network. The vulnerability essentially allows the application to function as an open redirector, where any URL provided in the redirect parameters is accepted and processed without proper verification of its legitimacy or safety.
The operational impact of this vulnerability extends significantly beyond simple redirection capabilities, creating substantial security risks for organizations utilizing Cisco WebEx services. Attackers can leverage this flaw to conduct sophisticated phishing campaigns by redirecting users to malicious websites that mimic legitimate Cisco WebEx interfaces or other trusted corporate portals. The open redirect vulnerability enables man-in-the-middle attacks where users are unknowingly directed to attacker-controlled sites that can capture authentication credentials, install malware, or harvest sensitive information. Organizations may experience reputational damage, data breaches, and potential compliance violations when users fall victim to these phishing schemes. The vulnerability particularly affects enterprises that rely heavily on WebEx for business communications, as the redirect functionality could be exploited to compromise employee credentials or corporate data through social engineering attacks that appear legitimate.
Mitigation strategies for CVE-2015-4297 should prioritize immediate patching of affected Cisco WebEx MCS software versions, as Cisco released security advisories and patches specifically addressing this vulnerability. Organizations must implement network-level controls including web application firewalls and URL filtering mechanisms to detect and block suspicious redirect parameters. The implementation of proper input validation and output encoding within the WebEx application configuration can help prevent parameter manipulation. Security teams should also conduct comprehensive network monitoring to detect unusual redirect patterns and user behavior that might indicate exploitation attempts. Additionally, user education programs should emphasize the importance of verifying destination URLs before clicking on links, particularly in email communications or web-based collaboration platforms. This vulnerability aligns with CWE-601 open redirect weakness classification and represents a significant risk under the ATT&CK framework's initial access and credential access techniques, specifically targeting the use of phishing and social engineering methods to compromise user systems and gain unauthorized access to corporate networks.
The broader implications of this vulnerability highlight the critical importance of proper input validation and output encoding in web applications. Organizations should implement comprehensive security testing procedures including dynamic application security testing and manual penetration testing to identify similar weaknesses in their web applications. Regular security assessments of collaboration platforms and web-based services should include evaluation of redirect mechanisms and URL handling capabilities. The vulnerability also underscores the necessity of maintaining current security patches and implementing robust security monitoring systems to quickly detect and respond to exploitation attempts. Implementation of principle of least privilege access controls and network segmentation can help limit the potential impact if exploitation occurs, while also providing additional layers of defense against such open redirect vulnerabilities.