CVE-2026-27570 (GCVE-0-2026-27570)

Vulnerability from cvelistv5 – Published: 2026-03-19 20:52 – Updated: 2026-03-24 19:43
VLAI
Title
Discourse Vulnerable to Stored XSS via Shared AI Conversation Onebox
Summary
Discourse is an open-source discussion platform. Prior to versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2, the onebox method in the SharedAiConversation model renders the conversation title directly into HTML without proper sanitization. Versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 contain a patch. As a workaround, tighten access by changing the `ai_bot_public_sharing_allowed_groups` site setting.
Severity
5.1 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-24 19:32 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
References
Impacted products
Vendor Product Version CPE status
discourse discourse Affected: >= 2026.1.0-latest, < 2026.1.2
Affected: >= 2026.2.0-latest, < 2026.2.1
Affected: = 2026.3.0-latest
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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