7.2

CVE-2025-66281: qnap systems inc. qts NULL Pointer Dereference

CVSS: 7.2v3.1HighAnalyzed
Published 10-06-2026Last modified 10-06-2026
Open JSON

Vulnerability summary

CVE-2025-66281 is a high (CVSS 7.2) NULL Pointer Dereference vulnerability in qnap systems inc. qts. EPSS estimates a 0.46% chance of exploitation in the next 30 days, higher than 38.5% of scored vulnerabilities.

Overall risk
29/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.2/10
010
High · v3.1 (NVD)
EPSS score
0.46%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 10-06-2026
    PublishedVulnerability first disclosed.
  2. 10-06-2026
    Last modifiedVulnerability information updated.

Description

A NULL pointer dereference vulnerability has been reported to affect several QNAP operating system versions. The remote attackers can then exploit the vulnerability to launch a denial-of-service (DoS) attack. We have already fixed the vulnerability in the following versions: QTS 5.2.9.3410 build 20260214 and later QuTS hero h5.2.9.3410 build 20260214 and later QuTS hero h5.3.4.3500 build 20260520 and later QuTS hero h6.0.0.3397 build 20260206 and later

CVSS metrics

3 scores · 2 sources · 2 versions

EPSS trend

Probability

0.46%

Chance of exploitation in the next 30 days

Percentile

39%

Versus all other CVEs

30-day change

0.00 pp

From 0.46% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.46%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Qnap2 products
  • qts≥ 5.2.0.2737, < 5.2.9.3410
  • quts_hero≥ h5.2.0.2737, < h5.2.9.3410 | ≥ h5.3.0.3115, < h5.3.4.3500 | ≥ h6.0.0.3324, < h6.0.0.3397
Qnap systems inc.2 products
  • qts≥ 5.2.0, < 5.2.9.3410 build 20260214
  • quts hero≥ h5.2.0, < h5.2.9.3410 build 20260214 | ≥ h5.3.0, < h5.3.4.3500 build 20260520 | ≥ ?, < h6.0.0.3397 build 20260206

2 vendors · 4 products

References

1 links