Description
Discourse is an open-source discussion platform. Prior to version 3.4.4 of the `stable` branch, version 3.5.0.beta5 of the `beta` branch, and version 3.5.0.beta6-dev of the `tests-passed` branch, Codepen is present in the default `allowed_iframes` site setting, and it can potentially auto-run arbitrary JS in the iframe scope, which is unintended. This issue is patched in version 3.4.4 of the `stable` branch, version 3.5.0.beta5 of the `beta` branch, and version 3.5.0.beta6-dev of the `tests-passed` branch. As a workaround, the Codepen prefix can be removed from a site's `allowed_iframes`.
CVSS Metrics
- Vector
- CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- Attack Vector
- network
- Complexity
- low
- Privileges
- none
- User Action
- none
- Confidentiality
- undefined
- Integrity
- undefined
- Availability
- undefined
- Weaknesses
- CWE-1038
Metadata
- Primary Vendor
- DISCOURSE
- Published
- 6/9/2025
- Last Modified
- 9/25/2025
- Source
- NIST NVD
- Note: Verify all details with official vendor sources before applying patches.
Affected Products
discourse : discoursediscourse : discoursediscourse : discoursediscourse : discoursediscourse : discoursediscourse : discourse
AI-Powered Remediation
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