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.

Attack Vector Network

Attack Complexity Low

Privileges Required None

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact Low

Vulnerable System Integrity Impact None

Vulnerable System Availability Impact None

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

No CVSS v3.1

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

The EPSS score is 0.00261.

Key SSVC decision points have not yet been added.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions
Veeam Backup for Microsoft 365 unaffected
Version Status Constraints
8.0 affected ≤ 8.6.0.1102

No data.

No data.

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Vendors Products
Veeam Subscribe
Backup For Microsoft 365 Subscribe

Project Subscriptions

Vendors Products
Veeam Subscribe
Backup For Microsoft 365 Subscribe
Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References
Link Providers
https://www.veeam.com/kb4957 cve-icon cve-icon
History

Wed, 28 Oct 2026 22:30:00 +0000

Type Values Removed Values Added
First Time appeared Veeam
Veeam backup For Microsoft 365
Vendors & Products Veeam
Veeam backup For Microsoft 365

Tue, 27 Oct 2026 18:15:00 +0000

Type Values Removed Values Added
Title Unauthenticated REST API Authentication Bypass via Forged Federation Token

Tue, 27 Oct 2026 16:30:00 +0000

Type Values Removed Values Added
Description 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.
Weaknesses CWE-347
References
Metrics cvssV4_0

{'score': 6.9, 'vector': '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'}

Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: hackerone

Published:

Updated: 2026-10-27T16:16:58.925Z

Reserved: 2026-10-06T15:00:00.655Z

Link: CVE-2026-106078

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-10-27T17:16:56.793

Modified: 2026-10-28T14:47:07.963

Link: CVE-2026-106078

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-10-28T22:12:19Z

Weaknesses