What is CVE-2026-40306?

CVE-2026-40306 is a medium-severity vulnerability in Dnnsoftware Dnn.platform, classified under Use of Insufficiently Random Values. CVSS score: 6.5/10. Published 2026-04-17.

How severe is CVE-2026-40306?

Medium severity. CVSS v3 base score is 6.5 out of 10.

Vulnerability in Dnnsoftware Dnn.platform

CVE-2026-40306

DNN (formerly DotNetNuke) is an open-source web content management platform (CMS) in the Microsoft ecosystem. All new installations of DNN 10.x.x - 10.2.1 have the same Host GUID. This does not affect upgrades from 9.x.x. Version 10.2.2 patches the issue.

Published 2026-04-17 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.003 (20.3th percentile), scored 2026-10-19.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 20th percentile — 20.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001

Affected products

Dnnsoftware Dnn.platform — versions >= 10.0.0, < 10.2.2
Dnnsoftware Dotnetnuke

Weakness classification (CWE)

CWE-330 — Use of Insufficiently Random Values

References

github.com/dnnsoftware/Dnn.Platform/security/advisories/GHSA-2rhw-gw3f-477j (Vendor Advisory)
github.com/dnnsoftware/Dnn.Platform/releases/tag/v10.2.2 (Release Notes)

Frequently asked questions

What is CVE-2026-40306?: CVE-2026-40306 is a medium-severity vulnerability in Dnnsoftware Dnn.platform, classified under Use of Insufficiently Random Values. CVSS score: 6.5/10. Published 2026-04-17.
How severe is CVE-2026-40306?: Medium severity. CVSS v3 base score is 6.5 out of 10.