A vulnerability in Cisco WebEx browser extensions could allow an unauthenticated, remote attacker to execute arbitrary code with the privileges of the affected browser on an affected system.
The vulnerability is due to a design defect in an application programming interface (API) response parser within the plugin. An attacker that can convince an affected user to visit an attacker-controlled web page or follow an attacker-supplied link with an affected browser could exploit the vulnerability. If successful, the attacker could execute arbitrary code with the privileges of the affected browser.
Execution of arbitrary code
Vendor has released updates for Google Chrome, Firefox and internet explorer that address this vulnerability.