CVE-2017-12296 in WebEx Meetings Server
Summary
by MITRE
A vulnerability in Cisco WebEx Meetings Server could allow an unauthenticated, remote attacker to conduct a cross-site scripting (XSS) attack against a user of the affected system. The vulnerability is due to insufficient input validation of some parameters that are passed to the web server of the affected system. An attacker could exploit this vulnerability by convincing a user to follow a malicious link or by intercepting a user request and injecting malicious code into the request. A successful exploit could allow the attacker to execute arbitrary script code in the context of the affected web interface or allow the attacker to access sensitive browser-based information. Cisco Bug IDs: CSCvf51241, CSCvf51261.
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Analysis
by VulDB Data Team • 01/19/2021
The vulnerability identified as CVE-2017-12296 represents a critical cross-site scripting flaw within Cisco WebEx Meetings Server, a widely deployed collaboration platform that facilitates video conferencing and meeting management. This vulnerability stems from inadequate input validation mechanisms within the web server component of the affected system, creating an exploitable entry point for remote attackers who require no authentication credentials to initiate malicious activities. The flaw specifically targets parameter handling within the web interface, where user-supplied inputs are not sufficiently sanitized before being processed and rendered back to users. The vulnerability's impact is particularly concerning given the widespread adoption of WebEx Meetings Server in enterprise environments where sensitive business communications and data exchanges occur regularly.
The technical exploitation of this vulnerability occurs through the manipulation of web parameters that are processed by the affected web server. Attackers can craft malicious links or intercept legitimate user requests to inject malicious script code that executes within the victim's browser context when they interact with the compromised system. This type of attack leverages the fundamental principle of XSS vulnerabilities where untrusted data is incorporated into web pages without proper validation or encoding, allowing malicious scripts to run with the privileges of the authenticated user. The vulnerability is classified as a classic stored or reflected XSS issue depending on how the malicious input is processed and stored within the system, with potential for session hijacking, credential theft, or data exfiltration. The Cisco bug IDs CSCvf51241 and CSCvf51261 specifically reference the underlying code flaws that enable this attack vector.
The operational impact of CVE-2017-12296 extends beyond simple script execution, as successful exploitation can lead to complete browser compromise and unauthorized access to sensitive information. Attackers can leverage this vulnerability to steal session cookies, capture user credentials, or redirect victims to malicious sites that appear legitimate. The risk is amplified in enterprise environments where WebEx Meetings Server is used for sensitive business meetings, internal communications, and collaborative workspaces that may contain confidential data. Organizations utilizing this platform face potential data breaches, unauthorized access to meeting recordings, and compromise of business-critical communications. The vulnerability's remote nature means that attackers can exploit it from anywhere on the internet without requiring physical access or network proximity to the target system, making it particularly dangerous for organizations with distributed workforces or remote access capabilities.
Security mitigations for this vulnerability should prioritize immediate patch management and implementation of web application firewalls to filter malicious inputs before they reach the vulnerable web server. Organizations should implement strict input validation controls and output encoding mechanisms to prevent malicious scripts from executing within the browser context. Network segmentation and monitoring solutions can help detect anomalous traffic patterns that may indicate exploitation attempts. The vulnerability aligns with CWE-79 which specifically addresses cross-site scripting flaws in web applications, and maps to ATT&CK techniques including T1059 for command and scripting interpreter and T1566 for spearphishing attacks that leverage XSS vulnerabilities. Regular security assessments and penetration testing should be conducted to identify similar input validation weaknesses in other web applications within the organization's attack surface. Additionally, user education programs should emphasize the importance of verifying links and avoiding suspicious communications that may contain malicious payloads designed to exploit such vulnerabilities.