CVE-2025-62839
Hard-coded Cryptographic Key #1
An use of hard-coded cryptographic key vulnerability has been reported to affect HBS 3 Hybrid Backup Sync and Hybrid Backup Sync. If exploited, the vulnerability could allow remote attackers to compromise the security of the system.
We have already fixed the vulnerability in the following version: HBS 3 Hybrid Backup Sync 26.4.0.521 and later Hybrid Backup Sync 26.4.0.521 and later Hybrid Backup Sync 26.4.1.563 and later
Attack profile
How easy it is to exploit
- Attack vector
- Adjacent network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
8.7
Hard-coded Cryptographic Key #1
An use of hard-coded cryptographic key vulnerability has been reported to affect HBS 3 Hybrid Backup Sync and Hybrid Backup Sync. If exploited, the vulnerability could allow remote attackers to compromise the security of the system.
We have already fixed the vulnerability in the following version: HBS 3 Hybrid Backup Sync 26.4.0.521 and later Hybrid Backup Sync 26.4.0.521 and later Hybrid Backup Sync 26.4.1.563 and later
- Record
CVE-2025-62839- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - Weakness
- CWE-321
- Updated
- 2026-11-02
EUVDEUVD-2025-211208
8.7
An use of hard-coded cryptographic key vulnerability has been reported to affect HBS 3 Hybrid Backup Sync and Hybrid Backup Sync. If exploited, the vulnerability could allow remote attackers to compromise the security of the system.
We have already fixed the vulnerability in the following version: HBS 3 Hybrid Backup Sync 26.4.0.521 and later Hybrid Backup Sync 26.4.0.521 and later Hybrid Backup Sync 26.4.1.563 and later
- Record
EUVD-2025-211208- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-7m89-78rx-fg5j
8.7
An use of hard-coded cryptographic key vulnerability has been reported to affect HBS 3 Hybrid...
An use of hard-coded cryptographic key vulnerability has been reported to affect HBS 3 Hybrid Backup Sync and Hybrid Backup Sync. If exploited, the vulnerability could allow remote attackers to compromise the security of the system.
We have already fixed the vulnerability in the following version: HBS 3 Hybrid Backup Sync 26.4.0.521 and later Hybrid Backup Sync 26.4.0.521 and later Hybrid Backup Sync 26.4.1.563 and later
- Record
GHSA-7m89-78rx-fg5j- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - Weakness
- CWE-321
- Updated
- 2026-11-02
NVD
8.7
An use of hard-coded cryptographic key vulnerability has been reported to affect HBS 3 Hybrid Backup Sync and Hybrid Backup Sync. If exploited, the vulnerability could allow remote attackers to compromise the security of the system.
We have already fixed the vulnerability in the following version: HBS 3 Hybrid Backup Sync 26.4.0.521 and later Hybrid Backup Sync 26.4.0.521 and later Hybrid Backup Sync 26.4.1.563 and later
- Record
CVE-2025-62839- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - Weakness
- CWE-321
- Updated
- 2026-11-04
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| facts | NVD | |
| first indexed | CVE List, EUVD, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2025-62839 is a high vulnerability (CVSS 8.7) in Qnap Systems Inc. Hbs 3 Hybrid Backup Sync, published October 29, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.24%, the 15th percentile. No source names a fixed version.