# CVE-2025-64394: CVE-2025-64394

Status: published. Published: 2026-10-27. Updated: 2026-11-04.

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 remediation reported in collected sources

## Affected products and versions

- Veeam / Backup for Microsoft 365: ≥ 8.0; ≤ 8.6.0.1102 (affected, semver). Source: CNA: hackerone

## Severity and prioritization

- CVSS 4.0: 4.3 (medium); 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; source: CNA: hackerone

- CISA KEV: No listing in collected sources

- EPSS: 0.11% as of 2026-11-04; percentile 1.16%

- SSVC: exploitation none; automatable no; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-1386

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://www.veeam.com/kb4957 (CNA: hackerone)

## Provenance

- CNA: hackerone: https://www.cve.org/CVERecord?id=CVE-2025-64394; retrieved 2026-11-04; source updated 2026-11-04

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2025-64394; retrieved 2026-11-04; source updated Not reported

Revision: e8c97ee22da500a93e186978e6d3c26e6bf53e351a44907eedb15809f7370ef3

Canonical: https://y2.dev/cve/CVE-2025-64394

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Collected public records only. Check source status for coverage and freshness.