Cisco WebEx Browser Extension CVE-2017-6753 Remote Code Execution Vulnerability



Date Discovered

July 17, 2017


Cisco WebEx Browser Extension is prone to a remote code-execution vulnerability. Successfully exploiting this issue will allow attackers to execute arbitrary code within the context of the application. This issue is being tracked by Cisco Bug IDs CSCvf15012, CSCvf15020, CSCvf15030, CSCvf15033, CSCvf15036, and CSCvf15037. The following products are affected: Versions prior to 1.0.12 of the Cisco WebEx extension on Google Chrome. Versions prior to 1.0.12 of the Cisco WebEx extension on Mozilla Firefox.

Technologies Affected

  • Cisco WebEx Extension 1.0.2
  • Cisco WebEx Extension 1.0.3
  • Cisco WebEx Extension 1.0.5
  • Cisco WebEx Extension 1.0.9
  • Cisco WebEx Meetings Server 2.7
  • Cisco WebEx Meetings Server 2.8
  • Cisco WebEx Meetings Server T29_orion_merge
  • Cisco WebEx Meetings T29
  • Cisco WebEx Meetings T30
  • Cisco WebEx Meetings T31
  • Cisco WebEx Meetings T32


Block external access at the network boundary, unless external parties require service.
Filter access to the affected computer at the network boundary if global access isn't needed. Restricting access to only trusted computers and networks might greatly reduce the likelihood of a successful exploit.

Deploy network intrusion detection systems to monitor network traffic for malicious activity.
Deploy NIDS to monitor network traffic for signs of anomalous or suspicious activity including unexplained incoming and outgoing traffic. This may indicate exploit attempts or activity that results from successful exploits.

Updates are available. Please see the references or vendor advisory for more information.



Tavis Ormandy of Google Project Zero and Cris Neckar of Divergent Security.

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