When linking a Nessus scanner or agent to Tenable.io or other manager, Nessus 6.x before 6.11 does not verify the manager's TLS certificate when making the initial outgoing connection. This could allow man-in-the-middle attacks.

VMware vCenter Server (6.7 before 6.7u3, 6.6 before 6.5u3k) contains a session hijack vulnerability in the vCenter Server Appliance Management Interface update function due to a lack of certificate validation. A malicious actor with network positioning between vCenter Server and an update repository may be able to perform a session hijack when the vCenter Server Appliance Management Interface is used to download vCenter updates.

A vulnerability in the SSL implementation of the Cisco Intelligent Proximity solution could allow an unauthenticated, remote attacker to view or alter information shared on Cisco Webex video devices and Cisco collaboration endpoints if the products meet the conditions described in the Vulnerable Products section. The vulnerability is due to a lack of validation of the SSL server certificate received when establishing a connection to a Cisco Webex video device or a Cisco collaboration endpoint. An attacker could exploit this vulnerability by using man in the middle (MITM) techniques to intercept the traffic between the affected client and an endpoint, and then using a forged certificate to impersonate the endpoint. Depending on the configuration of the endpoint, an exploit could allow the attacker to view presentation content shared on it, modify any content being presented by the victim, or have access to call controls. This vulnerability does not affect cloud registered collaboration endpoints.

A TLS certificate validation flaw was found in Elastic APM agent for Ruby versions before 2.9.0. When specifying a trusted server CA certificate via the 'server_ca_cert' setting, the Ruby agent would not properly verify the certificate returned by the APM server. This could result in a man in the middle style attack against the Ruby agent.