BoletimSecAugust 28, 2026🇵🇹Translated from Portuguese

Critical Veeam ONE Flaw Allows Remote Attackers to Expose Service Account Credentials via Forced SMB Authentication

Veeam has addressed a critical vulnerability in Veeam ONE that could allow a remote unauthenticated attacker to force SMB authentication attempts from the platform's service account.

The flaw, tracked as CVE-2026-65641 and rated CVSS 9.3, affects Veeam ONE 13.1.0.7034 and all earlier builds in the 13.x series. Installations running the 12.x line are not vulnerable, according to the vendor.

By exploiting the issue, an attacker can redirect SMB authentication traffic to a server under their control. In Windows environments, this exposes Net-NTLM authentication material tied to the service account. The captured credentials can then be leveraged for offline password cracking attempts or NTLM relay attacks against other services.

The overall impact depends primarily on the permissions granted to the affected account. Risk is significantly higher when Veeam ONE operates with elevated privileges or maintains broad access to Active Directory, backup servers, hypervisors, and other critical infrastructure components.

Patches are now available in Veeam ONE 13.1 Patch 0 (build 13.1.0.7233) and Veeam ONE 13.0.2 Patch 1 (build 13.0.2.7159). Systems running earlier builds should be updated as a priority.

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