Veeam Security Advisory CVE-2022-26503

Veeam Software, Inc. had published a security advisory concerning Veeam Backup & Replication.

KB ID: 4289
Product: Veeam Agent for Microsoft Windows | 2.0 | 2.1 | 2.2 | 3.0.2 | 4.0 | 5.0 
Published: 2022-03-12 
Last modified: 2022-03-14 

Challenge
Vulnerability (CVE-2022-26503) in Veeam Agent for Microsoft Windows allows local privilege escalation. An attacker who successfully exploited this vulnerability could run arbitrary code with LOCAL SYSTEM privileges.

Severity: High
CVSS v3 score: 7.8

Cause
Veeam Agent for Microsoft Windows uses Microsoft .NET data serialization mechanisms. A local user may send malicious code to the network port opened by Veeam Agent for Windows Service (TCP 9395 by default), which will not be deserialized properly.

Solution
This vulnerability is fixed in the following Veeam Agent for Microsoft Windows patched releases:

• 5 (build 5.0.3.4708)

• 4 (build 4.0.2.2208)

Notes:

• For standalone Veeam Agent for Microsoft Windows deployments, the patched release must be installed manually on each machine.

• For Veeam Agent for Microsoft Windows deployments managed by Veeam Backup & Replication, the update can be performed from the Veeam Backup & Replication Console after installing the corresponding Veeam Backup & Replication cumulative patches ( 10a |  11a ).

  If a Auto-update backup agent is enabled, the Veeam Agent for Microsoft Windows deployments will be updated automatically. Otherwise, the update must be manually triggered in the Veeam Backup & Replication console.

• If you are using a version of Veeam Agent for Microsoft Windows prior to 4, please upgrade to a supported version.

More information
This vulnerability was reported by Nikita Petrov (Positive Technologies).