CVE-2015-4209 in WebEx Meeting Center
Summary
by MITRE
Cisco WebEx Meeting Center does not properly determine authorization for reading a host calendar, which allows remote attackers to obtain sensitive information by obtaining a list of all meetings and then sending a calendar request for each one, aka Bug ID CSCur23913.
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Analysis
by VulDB Data Team • 05/21/2022
The vulnerability identified as CVE-2015-4209 affects Cisco WebEx Meeting Center, a widely used web conferencing and collaboration platform that enables organizations to conduct virtual meetings and share content remotely. This security flaw represents a critical authorization bypass issue that undermines the platform's access control mechanisms and exposes sensitive calendar data to unauthorized parties. The vulnerability resides in the application's handling of calendar access permissions, specifically in how it validates user authorization when retrieving calendar information.
The technical implementation of this vulnerability stems from inadequate authorization checks within the calendar reading functionality of WebEx Meeting Center. When remote attackers exploit this flaw, they can enumerate all meetings within the system and subsequently request calendar details for each individual meeting. This systematic approach allows attackers to gather comprehensive information about scheduled meetings, including meeting times, participants, and potentially sensitive business-related details. The vulnerability essentially removes the proper access controls that should prevent unauthorized users from viewing calendar information that belongs to other users or organizations.
The operational impact of this vulnerability extends beyond simple information disclosure, as it creates opportunities for more sophisticated attacks. Attackers can use the gathered calendar information to plan social engineering campaigns, identify business patterns, or target specific individuals for further exploitation. The exposure of meeting schedules can reveal organizational structures, key personnel involvement in projects, and business timing patterns that adversaries could leverage for financial gain or competitive advantage. This type of information disclosure aligns with CWE-284, which describes improper access control issues, and represents a classic case of insufficient authorization validation.
Organizations using Cisco WebEx Meeting Center face significant risks from this vulnerability, particularly those in regulated industries or sectors where meeting confidentiality is paramount. The attack vector requires minimal technical expertise, making it accessible to a broad range of threat actors from casual script kiddies to organized cybercriminals. The vulnerability's persistence in the system means that once exploited, attackers can continue to harvest calendar information over time without detection. This aligns with ATT&CK technique T1083, which covers the discovery of system information through enumeration activities, and represents a fundamental failure in the principle of least privilege enforcement.
The recommended mitigations for CVE-2015-4209 include immediate deployment of Cisco's security patches and updates, which address the authorization bypass in the calendar access control mechanisms. Organizations should also implement network segmentation to limit access to WebEx services, enforce strict authentication controls, and conduct regular security assessments of their collaboration platforms. Additionally, administrators should review and tighten access controls for calendar features, implement monitoring for unusual calendar access patterns, and establish incident response procedures specifically for collaboration platform vulnerabilities. The remediation process should also include comprehensive user education about the risks of sharing sensitive information through web conferencing platforms and the importance of maintaining up-to-date security configurations.