HOMEVULNERABILITIESCVE-2026-40321
HIGH

CVE-2026-40321

CWE-87Published: April 17, 2026· Updated: Apr 24, 2026

8.0
CVSS v3.1
EPSS:0.04%probability of exploitation in 30 daysPercentile:12.4th

Official 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.

NVD Source

Technical Analysis

CVE-2026-40321 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 8.0.

The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorNetwork
Attack ComplexityHigh
Privileges Req.Low
User InteractionRequired
ScopeChanged
Impact
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:H

Affected Vendors & Products

dnnsoftware1 product
dotnetnuke
Source: NVD CPE · 1 total CPE entries

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
External links open in a new tab. Always verify in a controlled environment before use.

Official Patches & Advisories

All References (2)

Quick Facts

CVE IDCVE-2026-40321
CVSS Score8.0 / 10
SeverityHIGH
WeaknessCWE-87
CISA KEVNo
EPSS (30d)0.04%
Affected1 vendor
PublishedApr 17, 2026

Related CVEs (CWE-87)

Recommended Actions

  • Apply vendor patches immediately
  • Monitor CVE-2026-40321 in threat intel feeds
  • Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.
CVE-2026-40321 — CVSS 8.0 HIGH | CTIWATCH.COM