CVE-2026-40321

Description

DNN (formerly DotNetNuke) is an open-source web content management platform (CMS) in the Microsoft ecosystem. Prior to version 10.2.2, a user could upload a specially crafted SVG file that could include scripts that can target both authenticated and unauthenticated DNN users. The impact is increased if the scripts are run by a power user. Version 10.2.2 patches the issue.

CVSS v3.1 Score

8.0

HIGH

CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:H

EPSS — Exploit Prediction

0.0004

Probability of exploitation

0.13%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-87 CWE-87

Affected Products

Vendor	Product	Versions
dnnsoftware	dotnetnuke	< 10.2.2

References

Advisories & Patches

https://github.com/dnnsoftware/Dnn.Platform/security/advisories/GHSA-ffq7-898w-9jc4

Other References

https://github.com/dnnsoftware/Dnn.Platform/releases/tag/v10.2.2

Frequently Asked Questions

What is CVE-2026-40321? +

DNN (formerly DotNetNuke) is an open-source web content management platform (CMS) in the Microsoft ecosystem. Prior to version 10.2.2, a user could upload a specially crafted SVG file that could include scripts that can target both authenticated and unauthenticated DNN users. The impact is increased if the scripts are run by a power user. Version 10.2.2 patches the issue. It has a CVSS v3.1 base score of 8.0 (HIGH).

How severe is CVE-2026-40321? +

CVE-2026-40321 has a CVSS v3.1 score of 8.0 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0004, placing it in the 0th percentile for exploitation probability.

What products are affected by CVE-2026-40321? +

CVE-2026-40321 affects products from dnnsoftware, specifically: dotnetnuke. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2026-40321? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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