DNN Vulnerable to Stored Cross-Site Scripting (XSS) in the Prompt module

Description

Summary

The Prompt module allows execution of commands that can return raw HTML. Malicious input, even if sanitized for display elsewhere, can be executed when processed through certain commands, leading to potential script execution (XSS).

Description

The application sanitizes most user-submitted data before displaying it in entry forms. However, the Prompt module is capable of running commands whose output is treated as HTML. This creates a vulnerability where a malicious user can craft input containing embedded scripts or harmful markup.

If such malicious content is later processed by a Prompt command and returned as HTML, it bypasses the standard sanitation mechanisms. Simply executing a specific command through the Prompt module could render this untrusted data and cause unintended script execution in the browser specially in the context of a super-user.

Basic information

Type
reviewed
Severity
critical
Advisory on GitHub
Open advisory ↗
Repository advisory
Open repository advisory ↗
Source code
Browse source ↗
Published (advisory)
2025-09-23 15:09:19 UTC
Updated
2025-09-23 19:13:21 UTC
GitHub reviewed
2025-09-23 15:09:19 UTC
NVD published
2025-09-23

EPSS Score

Score Percentile
0.04% 12.67%

CVSS Scores

Base score Version Severity Vector
9.1 3.1
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.

Identifiers

CWEs

CWE id Name
CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Credits

  • bdukes (remediation_developer)
  • valadas (remediation_reviewer)
  • mitchelsellers (remediation_reviewer)

Affected packages (1)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem Package Vulnerable range First patched Vulnerable functions
nuget DotNetNuke.Core < 10.1.0 10.1.0

References

cvelogic Threat Intelligence