CVE-2019-1927 in WebEx Network Recording Player
Summary
by MITRE
Multiple vulnerabilities in Cisco Webex Network Recording Player for Microsoft Windows and Cisco Webex Player for Microsoft Windows could allow an attacker to execute arbitrary code on an affected system. The vulnerabilities exist because the affected software improperly validates Advanced Recording Format (ARF) and Webex Recording Format (WRF) files. An attacker could exploit these vulnerabilities by sending a user a malicious ARF or WRF file through a link or email attachment and persuading the user to open the file with the affected software on the local system. A successful exploit could allow the attacker to execute arbitrary code on the affected system with the privileges of the targeted user.
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Analysis
by VulDB Data Team • 11/21/2023
The vulnerability identified as CVE-2019-1927 represents a critical security flaw affecting Cisco Webex Network Recording Player and Cisco Webex Player software on Microsoft Windows systems. These media playback applications are designed to handle specific recording formats including Advanced Recording Format and Webex Recording Format, which are commonly used for storing and playing back video conference recordings. The flaw stems from inadequate input validation mechanisms within the software's file parsing routines, creating a path for malicious code execution when processing specially crafted media files. This vulnerability type falls under CWE-20, which specifically addresses improper input validation, making it a fundamental weakness in the software's security architecture that directly enables privilege escalation attacks.
The technical exploitation of this vulnerability occurs through a sophisticated social engineering campaign where attackers craft malicious ARF or WRF files designed to trigger buffer overflow conditions or other memory corruption vulnerabilities within the affected software. When a victim opens these malicious files using the vulnerable Webex players, the software's failure to properly validate file headers, structure, or content allows attackers to inject and execute arbitrary code within the context of the user's privileges. This execution model aligns with ATT&CK technique T1204.002, which describes user execution through spearphishing attachments, demonstrating how the vulnerability creates an ideal attack vector for targeted campaigns. The privilege escalation aspect means that successful exploitation could allow attackers to gain full control over the victim's system, potentially leading to data exfiltration, lateral movement, or persistent access within the network environment.
The operational impact of CVE-2019-1927 extends beyond individual system compromise to potentially affect entire enterprise networks where Webex collaboration tools are widely deployed. Organizations utilizing Cisco Webex for video conferencing, training sessions, or remote collaboration may find their security posture significantly weakened if users inadvertently open malicious recordings, particularly in environments where email filtering may not adequately detect such threats. The vulnerability's exploitation requires minimal technical sophistication from attackers, making it particularly dangerous in enterprise settings where users may not be adequately trained to recognize suspicious file attachments. Security professionals should consider this vulnerability as part of broader attack surface management strategies, especially when evaluating the security of collaboration and communication platforms that handle user-generated content.
Mitigation strategies for CVE-2019-1927 should focus on immediate software patching as the primary defense mechanism, with organizations prioritizing the deployment of Cisco's official security updates. Network administrators should implement additional layers of protection including email filtering solutions that can detect and block suspicious file attachments, particularly those with ARF or WRF extensions. The implementation of application whitelisting policies can prevent unauthorized execution of vulnerable software, while user education programs should emphasize the dangers of opening unexpected media files from untrusted sources. Security monitoring should include detection of unusual file access patterns or execution of potentially malicious code within the Webex player processes, and incident response procedures should be updated to address potential exploitation attempts. Organizations should also consider temporary network segmentation or access controls that limit the ability of potentially compromised systems to communicate with critical network resources until full patching is completed.