Veeam warns to install patches to fix a bug in Backup & Replication

Veeam Backup & Replication (VBR) contains a missing-authentication flaw (CWE-306) in its Cloud Connect component that lets an unauthenticated network attacker obtain encrypted credentials stored in VBR's configuration database. It is triggered simply by connecting to the exposed service, because the function that serves credential material performs no authentication check; no privileges or user interaction are required (CVSS 3.1: 7.5, network vector). With the recovered credentials, an attacker can gain access to backup infrastructure hosts, which has been used as an entry point and pivot for ransomware operations. Any organization running Veeam Backup & Replication is potentially affected, with the greatest risk where the VBR/Cloud Connect service is reachable from the internet. Exploitation is confirmed: CISA added the bug to its KEV catalog on 2023-08-22 with known ransomware use, the Cuba ransomware group has been observed stealing credentials through this exploit, and EPSS assigns a 77.6% near-term exploitation probability (100th percentile).

Do: Apply the fixes Veeam provides in its security advisory immediately — per CISA's KEV listing, patch per vendor instructions or discontinue use — prioritizing internet-facing Cloud Connect servers. After patching, rotate all credentials stored in the configuration database, since they should be considered exposed, and review those accounts for signs of misuse. Restrict network access to the VBR service from untrusted networks and check servers for exploitation indicators such as unexpected connections to the service or anomalous logins with stored credentials.