CVE-2021-27876
Description
An issue was discovered in Veritas Backup Exec before 21.2. The communication between a client and an Agent requires successful authentication, which is typically completed over a secure TLS communication. However, due to a vulnerability in the SHA Authentication scheme, an attacker is able to gain unauthorized access and complete the authentication process. Subsequently, the client can execute data management protocol commands on the authenticated connection. By using crafted input parameters in one of these commands, an attacker can access an arbitrary file on the system using System privileges.
Summary dbcve.org
Veritas Backup Exec before version 21.2 contains a vulnerability in the SHA Authentication scheme used between clients and Agents. An attacker can bypass the authentication mechanism over TLS and subsequently execute data management protocol commands on the authenticated connection. By crafting specific input parameters in these commands, an attacker can read arbitrary files on the system with System-level privileges.
Mitigation
Upgrade Veritas Backup Exec to version 21.2 or later to remediate this vulnerability. If immediate patching is not possible, restrict network access to Backup Exec agents and monitor for unauthorized authentication attempts.