A vulnerability in Cisco Webex Meetings and Cisco Webex Meetings Server could allow an unauthenticated, remote attacker to maintain bidirectional audio despite being expelled from an active Webex session. The vulnerability is due to a synchronization issue between meeting and media services on a vulnerable Webex site. An attacker could exploit this vulnerability by sending crafted requests to a vulnerable Cisco Webex Meetings or Cisco Webex Meetings Server site. A successful exploit could allow the attacker to maintain the audio connection of a Webex session despite being expelled.
The product utilizes multiple threads or processes to allow temporary access to a shared resource that can only be exclusive to one process at a time, but it does not properly synchronize these actions, which might cause simultaneous accesses of this resource by multiple threads or processes.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Webex_meetings_server | Cisco | * | 3.0 (excluding) |
| Webex_meetings_server | Cisco | 3.0-maintenance_release2 (including) | 3.0-maintenance_release2 (including) |
| Webex_meetings_server | Cisco | 3.0-maintenance_release3 (including) | 3.0-maintenance_release3 (including) |
| Webex_meetings_server | Cisco | 4.0 (including) | 4.0 (including) |
| Webex_meetings_server | Cisco | 4.0-maintenance_release1 (including) | 4.0-maintenance_release1 (including) |
| Webex_meetings_server | Cisco | 4.0-maintenance_release2 (including) | 4.0-maintenance_release2 (including) |
Synchronization refers to a variety of behaviors and mechanisms that allow two or more independently-operating processes or threads to ensure that they operate on shared resources in predictable ways that do not interfere with each other. Some shared resource operations cannot be executed atomically; that is, multiple steps must be guaranteed to execute sequentially, without any interference by other processes. Synchronization mechanisms vary widely, but they may include locking, mutexes, and semaphores. When a multi-step operation on a shared resource cannot be guaranteed to execute independent of interference, then the resulting behavior can be unpredictable. Improper synchronization could lead to data or memory corruption, denial of service, etc.