External risk intelligence

Veritas Backup Exec Agent Command Execution Vulnerability

CVE advisoryKnown Exploit

CVE-2021-27878

A flaw in Veritas Backup Exec Agent's authentication allows unauthorized access and arbitrary command execution with system privileges. This poses a risk of data compromise and operational disruption to affected organizations.

2Halo Surface Signal

Veritas Backup Exec

before 21.2

External exposure likelihood

Halo Surface Signal score for CVE-2021-27878

The vulnerability affects Veritas Backup Exec Agent, which is typically deployed within internal network segments to facilitate communication between backup servers and clients. While network-reachable within an organization's environment, these agents are rarely exposed directly to the public internet by design.

Horizon Alert

Summary of the vulnerability and why it matters

The Veritas Backup Exec Agent contains a flaw in its authentication process that could allow unauthorized access. This weakness enables an attacker to execute arbitrary commands on the system with elevated privileges. The primary business impact involves potential data loss or corruption, unauthorized system modifications, and compromised business operations.

  • Vulnerable component: Veritas Backup Exec Agent
  • Core weakness: Flawed authentication scheme
  • Main business impact: Command execution and data compromise

Attack Path

How an attacker could exploit the issue

Attackers can exploit a vulnerability in Veritas Backup Exec to gain unauthorized access and execute arbitrary commands on a system. This occurs when an attacker leverages a weakness in the SHA Authentication scheme to bypass typical secure communication protocols between a client and an Agent. Once authenticated, the attacker can use data management protocol commands to achieve command execution with system privileges, potentially impacting data integrity and system operations.

  • Network exposure, unauthenticated access.
  • Attacker gains unauthorized authentication.
  • Attacker executes arbitrary commands.

Live Threat

Current exploitation, exposure, and threat context

This vulnerability presents a significant risk to organizations utilizing Veritas Backup Exec. An attacker with low technical skill could exploit this by gaining unauthorized access through a weakened authentication process. Successful exploitation allows the attacker to execute arbitrary commands with system privileges, potentially leading to data compromise, system disruption, or further network infiltration.

  • Likely attacker skill level: Low
  • Required access or conditions: Network access, low privileges
  • Business risk or urgency: High, requires immediate attention

Priority actions

Operational Fix

Recommended remediation, mitigation, and detection steps

An authentication vulnerability in Veritas Backup Exec Agent allows an attacker to gain unauthorized access and execute arbitrary commands with system privileges. This poses a significant risk to affected organizations, potentially leading to data compromise and system control. Immediate action is recommended to mitigate this risk.

  • Identify all Veritas Backup Exec Agent installations.
  • Limit network access to affected systems.
  • Apply vendor updates and confirm remediation.
  • Monitor for related malicious activity.

Frequently asked questions

What is Veritas Backup Exec Agent and its role in data management?

Veritas Backup Exec Agent is a component of Veritas Backup Exec software. It enables communication between backup servers and client machines, facilitating data backup and recovery operations within an organization's IT infrastructure. This agent is crucial for ensuring that data can be effectively protected and restored when needed.

What kind of vulnerability does CVE-2021-27878 represent in Veritas Backup Exec?

CVE-2021-27878 is an authentication bypass vulnerability. It exploits a flaw in the SHA Authentication scheme, allowing an attacker to complete the authentication process without proper credentials, leading to unauthorized access.

How can an attacker exploit the SHA Authentication weakness in Veritas Backup Exec?

An attacker can exploit the SHA Authentication scheme weakness by bypassing the usual secure TLS communication. This allows them to gain unauthorized authentication and then use data management protocol commands over the established connection to execute arbitrary commands with system privileges.

What is the relevance of the Veritas Backup Exec vulnerability (CVE-2021-27878) concerning external threats?

While the vulnerability affects Veritas Backup Exec Agent, which is usually internal, its network-based attack vector means it can be exploited if accessible. The Halo Surface Signal indicates this is unlikely to be directly exposed to the public internet, but its impact warrants attention if any network access is possible.

What practical steps should be taken to respond to the Veritas Backup Exec authentication vulnerability?

To address this vulnerability, organizations should identify all Veritas Backup Exec Agent installations, restrict network access to these systems, and promptly apply vendor-provided updates. Confirming that the remediation has been successful and monitoring for any suspicious activity are also critical steps.

References