# CVE-2025-62842: HBS 3 Hybrid Backup Sync

> Attackers with local network access can read or modify files via path traversal in QNAP HBS 3 Hybrid Backup Sync.

- **Severity:** High 7.0 (`CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 2 Jan 2026
- **Updated:** 5 Jan 2026
- **Also known as:** GHSA-mgp4-g6w6-2q2x

## What is CVE-2025-62842?

CVE-2025-62842 is a high-severity path traversal vulnerability in QNAP Systems Inc. HBS 3 Hybrid Backup Sync, published on 2 Jan 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official 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

Weakness: CWE-73 (External Control of File Name or Path)

## Which versions are affected by CVE-2025-62842?

It affects 1 product.


Products: Qnap Hybrid Backup Sync.

## How do I fix CVE-2025-62842?

No fix has been published for CVE-2025-62842 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-62842 being exploited?

There is no known exploitation of CVE-2025-62842 in the wild and no public exploit code.

## Other vulnerabilities in QNAP Systems Inc. HBS 3 Hybrid Backup Sync

- [CVE-2021-28799](https://insights.sbomify.com/CVE-2021-28799/): QNAP NAS Improper Authorization (critical 10.0, exploited in the wild)
- [CVE-2021-28809](https://insights.sbomify.com/CVE-2021-28809/): Missing Authentication for Critical Function in RTRR Server in HBS3 (critical 9.8)
- [CVE-2024-50388](https://insights.sbomify.com/CVE-2024-50388/): HBS 3 Hybrid Backup Sync (critical 9.5)
- [CVE-2025-62840](https://insights.sbomify.com/CVE-2025-62840/): HBS 3 Hybrid Backup Sync (high 7.0)
- [CVE-2024-53695](https://insights.sbomify.com/CVE-2024-53695/): HBS 3 Hybrid Backup Sync (medium 6.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-62842 and fix it if it is affected.

What it is: CVE-2025-62842 is a high-severity path traversal vulnerability in QNAP Systems Inc. HBS 3 Hybrid Backup Sync, published on 2 Jan 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-62842 in the wild and no public exploit code.

Affected product: QNAP Systems Inc. HBS 3 Hybrid Backup Sync. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2025-62842/ (Markdown: https://insights.sbomify.com/CVE-2025-62842/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-62842
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-62842
- OSV: https://osv.dev/vulnerability/CVE-2025-62842

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-62842/
Summaries are generated and may contain mistakes; the official description above is the record.