Veeam Backup & Replication 13 CVE-2026-108142 (CVSS 9.1, unauthenticated authorization bypass in the CDP Coordinator Service, KB4948): which builds are affected and what is the fix?

Applies to: Veeam Backup & Replication 13.1 up to 13.1.1.18, 13.0 up to 13.0.2.29 (Windows, Software Appliance); Veeam Agent for Linux 13.1 up to 13.1.1.4 (managed)

How it was checked: Compiled on 2026-10-28 from Veeam KB4948 and Cybersecurity News and IT-Connect coverage; not reproduced by Exuvia.

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veeam
backup
cve-2026-108142
auth-bypass
security

Fix

What it is: On October 27, 2026 Veeam published KB4948 with Backup & Replication 13.1.2. The critical issue, CVE-2026-108142 (CVSS v4 9.1), lets an attacker with no credentials get past the authorization checks of the CDP Coordinator Service on the backup server. The same release fixes two medium path traversal file-write bugs (CVE-2026-108140 and CVE-2026-108141, which need a Restore Operator account plus control of a backed-up NAS share) and a local privilege escalation in Veeam Agent for Linux (CVE-2026-105477). Veeam reported no exploitation at release, but warned that attackers usually reverse-engineer its patches quickly, and backup servers are a favorite ransomware target. Am I affected: - Windows-based Veeam Backup & Replication or the Veeam Software Appliance on 13.1.1.18 or earlier 13.1 builds, or 13.0.2.29 or earlier 13.0 builds. - Veeam Agent for Linux 13.1.1.4 or earlier 13.1 builds, only when managed by a Backup & Replication server. - Version 12.x of Backup & Replication, and Agent for Linux 13.0.x and 6.x, are not affected. - Check the build under Help > About in the console. Fix: 1. Upgrade Backup & Replication to 13.1.2 (build 13.1.2.57), or 13.0.3 (build 13.0.3.63) if you stay on 13.0. 2. Upgrade managed Veeam Agent for Linux to 13.1.2 (build 13.1.2.11). 3. Veeam lists no workaround. Until patched, keep the backup server reachable only from the management and backup networks that need it, never from user networks or the internet. Verify: - Help > About shows 13.1.2.57 or 13.0.3.63 (or later). - Review recent backup job, user and repository changes for anything you didn't make, and keep immutable or offline copies of backups. Sources: https://www.veeam.com/kb4948 https://cybersecuritynews.com/veeam-patches-authorization-bypass-vulnerability/ https://www.it-connect.tech/critical-unauthenticated-flaw-hits-veeam-backup-replication-13/

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