CVE-2018-15446 in Meeting Server
Summary
by MITRE
A vulnerability in Cisco Meeting Server could allow an unauthenticated, remote attacker to gain access to sensitive information. The vulnerability is due to improper protections on data that is returned from user meeting requests when the Guest access via ID and passcode option is set to Legacy mode. An attacker could exploit this vulnerability by sending meeting requests to an affected system. A successful exploit could allow the attacker to determine the values of meeting room unique identifiers, possibly allowing the attacker to conduct further exploits.
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Analysis
by VulDB Data Team • 04/11/2020
The vulnerability identified as CVE-2018-15446 represents a critical information disclosure flaw within Cisco Meeting Server software that undermines the security posture of unified communications environments. This weakness specifically targets the system's handling of meeting room identifiers when guest access is configured in Legacy mode, creating an exploitable condition that allows remote attackers to extract sensitive operational data without authentication. The vulnerability stems from inadequate input validation and output sanitization mechanisms within the meeting request processing pipeline, where the system fails to properly restrict access to internal meeting room identification data that should remain confidential to authorized users only.
The technical implementation of this vulnerability manifests through the improper handling of user meeting requests when the Legacy guest access mode is enabled. When an attacker submits meeting requests to an affected Cisco Meeting Server instance, the system's response contains predictable meeting room unique identifiers that can be extracted and analyzed. This occurs because the application does not adequately validate or sanitize the data returned in response to these requests, allowing unauthorized access to internal system identifiers that are typically restricted to authenticated users. The flaw operates at the application layer and leverages the server's normal meeting request processing functions to expose sensitive information through routine operational interactions.
The operational impact of this vulnerability extends beyond simple information disclosure, as it enables attackers to conduct reconnaissance activities that can lead to more sophisticated exploitation attempts. By determining meeting room unique identifiers, an attacker gains valuable intelligence that can be used to plan targeted attacks against specific meeting rooms or to conduct broader enumeration campaigns across the entire system. This reconnaissance capability aligns with attack patterns described in the MITRE ATT&CK framework under the reconnaissance phase, where adversaries gather information about network infrastructure and services. The vulnerability can be exploited remotely without requiring any authentication credentials, making it particularly dangerous for organizations that rely on guest access functionality for collaborative meetings.
Organizations affected by this vulnerability should implement immediate mitigations including disabling Legacy guest access mode when possible, implementing network segmentation to restrict access to meeting server components, and applying the latest security patches provided by Cisco. The weakness maps to CWE-200, which describes improper output sanitization leading to information exposure, and represents a classic example of insufficient access control mechanisms in web applications. Security teams should also consider implementing monitoring solutions that can detect unusual patterns of meeting request submissions that may indicate exploitation attempts, as well as conducting regular security assessments to identify similar vulnerabilities in other communication platforms. The vulnerability demonstrates the critical importance of proper input validation and output sanitization in preventing information disclosure attacks that can compromise entire network infrastructures.