CVE-2025-64394

Privilege Escalation in Veeam Backup for Microsoft 365 via Installation File Write

Published Oct 27, 2026 CVSS 4.0 · 4.3 Medium EPSS < 1% KEV · Not listed
Description
A vulnerability allowing a low-privileged local user to write arbitrary files with SYSTEM privileges during the installation of Veeam Backup for Microsoft 365, which can lead to privilege escalation or denial of service.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
References
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Veeam
Veeam backup For Microsoft 365
Vendors & Products Veeam
Veeam backup For Microsoft 365
Type Values Removed Values Added
Title Privilege Escalation in Veeam Backup for Microsoft 365 via Installation File Write
Type Values Removed Values Added
Description A vulnerability allowing a low-privileged local user to write arbitrary files with SYSTEM privileges during the installation of Veeam Backup for Microsoft 365, which can lead to privilege escalation or denial of service.
Weaknesses CWE-1386
References
Metrics cvssV4_0

{'score': 4.3, 'vector': 'CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:A/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
hackerone
Published
Updated
Nov 4, 2026, 5:46 PM
Reserved
Oct 31, 2025, 3:00 PM
Status
Awaiting Analysis
Published
Oct 27, 2026, 5:16 PM
Modified
Nov 4, 2026, 6:17 PM