CVE-2025-66488 Discourse allows script execution in uploaded HTML/XML files on S3

Discourse is an open source discussion platform. A vulnerability present in versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0 affects anyone who uses S3 for uploads. While scripts may be executed, they will only be run in the context of the S3/CDN domain, with no site credentials...

CVE-2025-66488

Discourse (open source platform) has a vulnerability affecting installations using S3 for uploads, present in versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0. The issue allows script execution within the S3/CDN domain context when HTML/XML uploads are processed; no site credentials ar...

PT-2026-5176

Discourse is an open source discussion platform. A vulnerability present in versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0 affects anyone who uses S3 for uploads. While scripts may be executed, they will only be run in the context of the S3/CDN domain, with no site credentials...

PT-2026-5186

Name of the Vulnerable Software and Affected Versions Discourse versions prior to 3.5.4 Discourse versions prior to 2025.11.2 Discourse versions prior to 2025.12.1 Discourse versions prior to 2026.1.0 Description Discourse is an open source discussion platform. Users archives are viewable by user...

CVE-2025-68662: Server-Side Request Forgery (SSRF)

Discourse is an open source discussion platform. In versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0, a hostname validation issue in FinalDestination could allow bypassing SSRF protections under certain conditions. This issue is patched in versions 3.5.4, 2025.11.2, 2025.12.1, and...

CVE-2026-21865: Missing Authorization

Discourse is an open source discussion platform. In versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0, moderators can convert some personal messages to public topics when they shouldn't have access. This issue is patched in versions 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0. As a...

PT-2026-5182

Name of the Vulnerable Software and Affected Versions Discourse versions prior to 3.5.4 Discourse versions prior to 2025.11.2 Discourse versions prior to 2025.12.1 Discourse versions prior to 2026.1.0 Description Discourse is an open source discussion platform. Certain subscription endpoints do n...

Discourse security vulnerabilities

Discourse is an open-source community discussion platform developed by Discourse. This platform includes features such as communities, email, and chat rooms. Vulnerabilities exist in versions of Discourse prior to 3.5.4, as well as versions before 2025.11.2, 2025.12.1, and 2026.1.0. These...

Discourse Information Leakage Vulnerability

Discourse is an open-source community discussion platform developed by Discourse. This platform includes features such as communities, email communication, and chat rooms. Versions of Discourse prior to 3.5.4, as well as versions before 2025.11.2, 2025.12.1, and 2026.1.0, have a vulnerability...

CVE-2025-68666: Incorrect Authorization

Discourse is an open source discussion platform. In versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0, users archives are viewable by users with moderation privileges even though moderators should not have access to the archives. Private topic/post content made by the users are leaked...

Discourse security vulnerabilities

Discourse is an open-source community discussion platform developed by Discourse. This platform includes features such as communities, email communication, and chat rooms. Vulnerabilities exist in versions of Discourse prior to 3.5.4, as well as versions prior to 2025.11.2, 2025.12.1, and 2026.1....

CVE-2025-67723: Improper Neutralization of Input During Web Page Generation

Discourse is an open source discussion platform. Versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0 have a content-security-policy-mitigated cross-site scriptinv vulnerability on the Discourse Math plugin when using its KaTeX variant. This issue is patched in versions 3.5.4, 2025.11.2,...

Discourse code vulnerabilities

Discourse is an open-source community discussion platform developed by Discourse. This platform includes features such as communities, email communication, and chat rooms. There were code vulnerabilities in versions of Discourse prior to 3.5.4, as well as versions prior to 2025.11.2, 2025.12.1, a...

PT-2026-5195

Name of the Vulnerable Software and Affected Versions Discourse versions prior to 3.5.4 Discourse versions prior to 2025.11.2 Discourse versions prior to 2025.12.1 Discourse versions prior to 2026.1.0 Description Discourse is an open source discussion platform. A privilege escalation issue exists...

CVE-2025-69289: Incorrect Authorization

Discourse is an open source discussion platform. A privilege escalation vulnerability in versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0 allows a non-admin moderator to bypass email-change restrictions, allowing a takeover of non-staff accounts. This issue is patched in versions 3.5.4...

Discourse security vulnerabilities

Discourse is an open-source community discussion platform developed by Discourse. This platform includes features such as communities, email communication, and chat rooms. Vulnerabilities exist in versions of Discourse prior to 3.5.4, as well as versions before 2025.11.2, 2025.12.1, and 2026.1.0...

Discourse security vulnerabilities

Discourse is an open-source community discussion platform developed by Discourse. This platform includes features such as communities, email, and chat rooms. Vulnerabilities exist in versions of Discourse prior to 3.5.4, as well as versions prior to 2025.11.2, 2025.12.1, and 2026.1.0. These...

CVE-2025-68479: Missing Authorization

Discourse is an open source discussion platform. In versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0, some subscription endpoints lack proper checking for ownership before making changes. This issue is patched in versions 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0. No known workarounds...

CVE-2025-68933: Incorrect Authorization

Discourse is an open source discussion platform. In versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0, non-admin moderators with the moderatorschangepostownership setting enabled can change ownership of posts in private messages and restricted categories they cannot access, then export...

CVE-2025-68934: Allocation of Resources Without Limits or Throttling

Discourse is an open source discussion platform. In versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0, authenticated users can submit crafted payloads to /drafts.json that cause On^2 processing in Base62.decode, tying up workers for 35-60 seconds per request. This affects all users as t...