CVE-2026-32243

Discourse: Stored XSS in discourse-ai shared conversations onebox

State
Published
Severity
5.3 Medium
Published
Mar 31, 2026
Updated
Apr 3, 2026
Reserved
Mar 11, 2026

Read the record on cve.org

Description

Discourse is an open-source discussion platform. From versions 2026.1.0-latest to before 2026.1.3, 2026.2.0-latest to before 2026.2.2, and 2026.3.0-latest to before 2026.3.0, an attacker with the ability to create shared AI conversations could inject arbitrary HTML and JavaScript via crafted conversation titles. This payload would execute in the browser of any user viewing the onebox preview, potentially allowing session hijacking or unauthorized actions on behalf of the victim. This issue has been patched in versions 2026.1.3, 2026.2.2, and 2026.3.0.

Scores

CVSSScoreVectorSource
4.05.3 MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:NGitHub_M
3.16.1 MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:NCISA-ADP

Weaknesses

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

Affected Products

ProductVersions
discoursediscourse
  • >= 2026.1.0-latest, < 2026.1.3Affected
  • >= 2026.2.0-latest, < 2026.2.2Affected
  • >= 2026.3.0-latest, < 2026.3.0Affected

References

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