CVE-2026-72728
Discourse: Onebox iframe origin allowlist enforces URL authority boundary
CVSS Score
6.3
EPSS Score
0.0%
EPSS Percentile
0th
Discourse is an open-source discussion platform. Prior to 2026.1.7, an authenticated user could submit specially formed URLs that bypassed the Onebox allowlist and embedded malicious content in a site. This issue is fixed in versions 2026.1.7, 2026.6.2, 2026.7.1, and 2026.8.0-latest.1.
| CWE | CWE-20 |
| Vendor | discourse |
| Product | discourse |
| Published | Aug 10, 2026 |
| Last Updated | Aug 10, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
Low
Availability
Low
Affected Versions
discourse / discourse
< 2026.1.7 >= 2026.6.0-latest, < 2026.6.2 >= 2026.7.0-latest, < 2026.7.1 >= 2026.8.0-latest, < 2026.8.0-latest.1