Hard-Coded Cryptographic Key Vulnerability in QNAP's Hybrid Backup Sync
CVE-2025-62839

8.7HIGH

Key Information:

Vendor

QNAP
Status
Hbs 3 Hybrid Backup Sync
Hybrid Backup Sync
Vendor
CVE Published:
29 October 2026

What is CVE-2025-62839?

A hard-coded cryptographic key vulnerability has been identified in QNAP's Hybrid Backup Sync products. This vulnerability permits remote attackers to potentially gain unauthorized access to the system, compromising its overall security. To mitigate this risk, it is crucial that users update to HBS 3 Hybrid Backup Sync version 26.4.0.521 or later, as well as Hybrid Backup Sync version 26.4.0.521 or later, or version 26.4.1.563 or later.

Affected Version(s)

HBS 3 Hybrid Backup Sync 26.4.x < 26.4.0.521

Hybrid Backup Sync 26.4.x < 26.4.0.521

Hybrid Backup Sync 26.4.x < 26.4.1.563

References

https://www.qnap.com/en/app-release-notes?keyword=HBS%203...
release-notes
https://www.qnap.com/en/app-release-notes?keyword=Hybrid&...
release-notes

CVSS V4

Score:
8.7
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Adjacent Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Team DDOS
.