CVE-2017-12359 in WebEx Network Recording Player
Summary
by MITRE
A Buffer Overflow vulnerability in Cisco WebEx Network Recording Player for Advanced Recording Format (.arf) files could allow an attacker to execute arbitrary code on a system. An attacker could exploit this vulnerability by providing a user with a malicious .arf file via email or URL and convincing the user to launch the file. Exploitation of this vulnerability could allow arbitrary code execution on the system of the targeted user. This vulnerability affects Cisco WebEx Business Suite meeting sites, Cisco WebEx Meetings sites, Cisco WebEx Meetings Server, and Cisco WebEx ARF players. Cisco Bug IDs: CSCve10729, CSCve10771, CSCve10779, CSCve11521, CSCve11543.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 12/11/2019
This buffer overflow vulnerability in Cisco WebEx Network Recording Player represents a critical security flaw that exploits improper input validation in the handling of Advanced Recording Format files. The vulnerability resides in the player's processing mechanism for .arf files, which are commonly used to store WebEx meeting recordings and contain multimedia content along with metadata. When a maliciously crafted .arf file is opened by the vulnerable player, the software fails to properly bounds-check data during parsing operations, leading to memory corruption that can be exploited to overwrite critical program memory regions.
The technical exploitation of this vulnerability follows a classic buffer overflow attack pattern where an attacker crafts a specially formatted .arf file containing malicious data that exceeds the allocated buffer space. This overflow can overwrite return addresses, function pointers, or other critical memory structures within the player application, allowing the attacker to redirect execution flow and inject arbitrary code. The vulnerability affects multiple Cisco WebEx platforms including business meeting sites, standard meeting sites, server installations, and client-side ARF players, indicating a widespread impact across the WebEx ecosystem. The attack vector relies on social engineering tactics where users are tricked into opening malicious files through email attachments or web links, making it particularly dangerous in enterprise environments where users may not be security-aware.
The operational impact of this vulnerability extends beyond simple code execution to potentially compromise entire user systems and network infrastructure. Successful exploitation could enable attackers to gain full system control, install persistent backdoors, escalate privileges, or use the compromised system as a launching point for further attacks within the network. Given that WebEx is widely used for business meetings and collaborative work, the potential for lateral movement and data exfiltration is significant. The vulnerability affects multiple Cisco Bug IDs including CSCve10729, CSCve10771, CSCve10779, CSCve11521, and CSCve11543, indicating that this flaw was present across different product versions and configurations, making it particularly challenging to secure comprehensively.
Organizations should implement immediate mitigations including disabling automatic playback of .arf files, implementing strict file type controls in email systems, and deploying network monitoring to detect suspicious file access patterns. The vulnerability aligns with CWE-121, which describes stack-based buffer overflow conditions, and maps to ATT&CK technique T1059.007 for command and scripting interpreter usage. Security teams should also consider network segmentation, endpoint protection solutions, and regular security awareness training for users to reduce the effectiveness of social engineering attacks. Patch management should be prioritized to ensure all affected Cisco WebEx installations receive the appropriate security updates from Cisco, as the vulnerability represents a persistent threat that could be exploited for extended periods if left unaddressed.