---
id: CVE-2026-106078
title: >-
  A vulnerability allowing an unauthenticated attacker to bypass REST API
  authentication with a forged federation token and receive responses from REST
  API endpoints that do not call the Veeam Backup for Microsoft 365 backup
  service.
summary: >-
  A vulnerability allowing an unauthenticated attacker to bypass REST API
  authentication with a forged federation token and receive responses from REST
  API endpoints that do not call the Veeam Backup for Microsoft 365 backup
  service.
severity: medium
cvss: 6.9
cvssVector: 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N'
cvssSource: cna
cwe:
  - CWE-347
vendor: Veeam
product: Backup for Microsoft 365
affected:
  - backup_for_microsoft_365 >= 8.0 <= 8.6.0.1102
published: '2026-10-27'
updated: '2026-10-27'
sourceUpdated: '2026-10-27T16:16:58.925Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-106078'
references:
  - url: 'https://www.veeam.com/kb4957'
tags:
  - cve.org
ingestedAt: '2026-10-27T16:32:34.388Z'
---

## Overview

A vulnerability allowing an unauthenticated attacker to bypass REST API authentication with a forged federation token and receive responses from REST API endpoints that do not call the Veeam Backup for Microsoft 365 backup service.

## Affected

- `backup_for_microsoft_365 >= 8.0 <= 8.6.0.1102`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.