How severe is CVE-2025-62842?

CVE-2025-62842 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2025-62842 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (13th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-62842?

CVE-2025-62842 affects Qnap Hybrid Backup Sync. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-62842?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2025-62842 have an EU (EUVD) identifier?

Yes. CVE-2025-62842 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-0662.

When was CVE-2025-62842 published?

CVE-2025-62842 was published on 2026-01-02 and last updated on 2026-06-17.

CVE-2025-62842

CVE-2025-62842 is a high-severity vulnerability in Qnap Hybrid Backup Sync with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-73.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v4: 7.0
EPSS exploit prediction: 0% (13th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-0662
Weakness: CWE-73
Affected product: Qnap Hybrid Backup Sync
Published: 2026-01-02
Last modified: 2026-06-17

Description

An external control of file name or path vulnerability has been reported to affect HBS 3 Hybrid Backup Sync. If an attacker gains local network access, they can then exploit the vulnerability to read or modify files or directories. We have already fixed the vulnerability in the following version: HBS 3 Hybrid Backup Sync 26.2.0.938 and later

Frequently asked questions

What is CVE-2025-62842?: An external control of file name or path vulnerability has been reported to affect HBS 3 Hybrid Backup Sync. If an attacker gains local network access, they can then exploit the vulnerability to read or modify files or directories. We have already fixed the vulnerability in the following version: HBS 3 Hybrid Backup Sync 26.2.0.938 and later
How severe is CVE-2025-62842?: CVE-2025-62842 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2025-62842 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (13th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-62842?: CVE-2025-62842 affects Qnap Hybrid Backup Sync. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-62842?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2025-62842 have an EU (EUVD) identifier?: Yes. CVE-2025-62842 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-0662.
When was CVE-2025-62842 published?: CVE-2025-62842 was published on 2026-01-02 and last updated on 2026-06-17.

References

https://www.qnap.com/en/security-advisory/qsa-25-46

Affected products (1)

cpe:2.3:a:qnap:hybrid_backup_sync:*:*:*:*:*:*:*:*

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