# CVE-2026-22899: QNAP File Station NULL pointer dereference in File Station 6

Source: https://junglewise.ai/threats/cve-2026-22899-qnap-file-station-null-pointer-dereference-in-file-station-6  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-10. Updated: 2026-06-10  
License: CC BY 4.0 with a link back

CVE-2026-22899 · Severity: info · CVSS 5.3 · Published 2026-06-10

QNAP File Station, a web-based application for managing files on QNAP NAS devices, is affected by a security flaw that could allow a user to crash the service. An attacker who already has a valid user account on the system can trigger this issue to cause a denial-of-service, making the file management interface unavailable to other users. This impact is limited to service availability and does not involve the theft of data or unauthorized access to files.

Technologies: [QNAP File Station](https://junglewise.ai/threats/technologies/file-station). Vendors: [QNAP](https://junglewise.ai/threats/vendors/qnap).

## Quick answers

**Is CVE-2026-22899 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-22899 being exploited in the wild.

**How severe is CVE-2026-22899?** Informational severity, with a CVSS score of 5.3, published 10 June 2026.

**Which products and versions are affected?** QNAP File Station Versions prior to 5.5.6.5208.

**Is there a fix for CVE-2026-22899?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-22899 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-22899?** Check whether you run QNAP File Station at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A NULL pointer dereference (CWE-476) exists in QNAP File Station 6. The vulnerability is reachable over the network but requires the attacker to possess valid user credentials (low privileges). By sending a specifically crafted request that triggers the NULL pointer dereference, an attacker can cause the application to crash, resulting in a denial-of-service. The vendor has released a fix in File Station version 5.5.6.5208 and later.

## Affected products

- QNAP File Station 6 Versions prior to 5.5.6.5208

## Timeline

- 2026-06-10: disclosed
- 2026-06-10: advisory

## References

- [https://www.qnap.com/en/security-advisory/qsa-26-19](https://www.qnap.com/en/security-advisory/qsa-26-19)

## Related threats

- [QNAP File Station 5 NULL pointer dereference](https://junglewise.ai/threats/cve-2026-24723-a-null-pointer-dereference-vulnerability-has-been-reported-to)
- [QNAP File Station 5 NULL pointer dereference](https://junglewise.ai/threats/cve-2026-24722-a-null-pointer-dereference-vulnerability-has-been-reported-to)
- [QNAP File Station 5 NULL pointer dereference](https://junglewise.ai/threats/cve-2026-24721-a-null-pointer-dereference-vulnerability-has-been-reported-to)
- [QNAP File Station resource exhaustion vulnerability](https://junglewise.ai/threats/cve-2026-24720-qnap-file-station-resource-exhaustion-vulnerability)
- [A cross-site scripting (XSS) vulnerability has been reported to affect File Station 5. If a remote attacker gains a…](https://junglewise.ai/threats/cve-2025-57706-a-cross-site-scripting-xss-vulnerability-has-been-reported-to)