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-2025-66488: Improper Encoding or Escaping of Output

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-2023-25169

discourse-yearly-review is a discourse plugin which publishes an automated Year in Review topic. In affected versions a user present in a yearly review topic that is then anonymised will still have some data linked to its original account. This issue has been patched in commit b3ab33bbf7 which is...

CVE-2023-49098

Discourse-reactions is a plugin that allows user to add their reactions to the post. Data about a user's reaction notifications could be exposed. This vulnerability was patched in commit 2c26939...

CVE-2023-49099

Discourse is a platform for community discussion. Under very specific circumstances, secure upload URLs associated with posts can be accessed by guest users even when login is required. This vulnerability has been patched in 3.2.0.beta4 and 3.1.4...

CVE-2023-31142

Discourse is an open source discussion platform. Prior to version 3.0.4 of the stable branch and version 3.1.0.beta5 of the beta and tests-passed branches, if a site has modified their general category permissions, they could be set back to the default. This issue is patched in version 3.0.4 of t...

CVE-2022-37458

Discourse through 2.8.7 allows admins to send invitations to arbitrary email addresses at an unlimited rate...

CVE-2022-31025

Discourse is an open source platform for community discussion. Prior to version 2.8.4 on the stable branch and 2.9.0beta5 on the beta and tests-passed branches, inviting users on sites that use single sign-on could bypass the mustapproveusers check and invites by staff are always approved...

CVE-2020-24327

Server Side Request Forgery SSRF vulnerability exists in Discourse 2.3.2 and 2.6 via the email function. When writing an email in an editor, you can upload pictures of remote websites...

CVE-2023-25167

Discourse is an open source discussion platform. In affected versions a malicious user can cause a regular expression denial of service using a carefully crafted git URL. This issue is patched in the latest stable, beta and tests-passed versions of Discourse. Users are advised to upgrade. There a...

CVE-2023-29196

Discourse is an open source platform for community discussion. This vulnerability is not exploitable on the default install of Discourse. A custom feature must be enabled for it to work at all, and the attacker’s payload must pass the CSP to be executed. However, if an attacker succeeds in...

CVE-2023-45806

Discourse is an open source platform for community discussion. Prior to version 3.1.3 of the stable branch and version 3.2.0.beta3 of the beta and tests-passed branches, if a user has been quoted and uses a | in their full name, they might be able to trigger a bug that generates a lot of duplicat...

CVE-2023-45147

Discourse is an open source community platform. In affected versions any user can create a topic and add arbitrary custom fields to a topic. The severity of this vulnerability depends on what plugins are installed and how the plugins uses topic custom fields. For a default Discourse installation...

CVE-2022-23549

Discourse is an option source discussion platform. Prior to version 2.8.14 on the stable branch and version 2.9.0.beta16 on the beta and tests-passed branches, users can create posts with raw body longer than the maxlength site setting by including html comments that are not counted toward the...

CVE-2022-23641

Discourse is an open source discussion platform. In versions prior to 2.8.1 in the stable branch, 2.9.0.beta2 in the beta branch, and 2.9.0.beta2 in the tests-passed branch, users can trigger a Denial of Service attack by posting a streaming URL. Parsing Oneboxes in the background job trigger an...

CVE-2022-23546

In version 2.9.0.beta14 of Discourse, an open-source discussion platform, maliciously embedded urls can leak an admin's digest of recent topics, possibly exposing private information. A patch is available for version 2.9.0.beta15. There are no known workarounds for this issue...

CVE-2022-23548

Discourse is an option source discussion platform. Prior to version 2.8.14 on the stable branch and version 2.9.0.beta16 on the beta and tests-passed branches, parsing posts can be susceptible to regular expression denial of service ReDoS attacks. This issue is patched in versions 2.8.14 and...

CVE-2022-31182

Discourse is the an open source discussion platform. In affected versions a maliciously crafted request for static assets could cause error responses to be cached by Discourse's default NGINX proxy configuration. A corrected NGINX configuration is included in the latest stable, beta and...

CVE-2022-31096

Discourse is an open source discussion platform. Under certain conditions, a logged in user can redeem an invite with an email that either doesn't match the invite's email or does not adhere to the email domain restriction of an invite link. The impact of this flaw is aggravated when the invite h...

CVE-2024-39320

Discourse is an open source discussion platform. Prior to 3.2.5 and 3.3.0.beta5, the vulnerability allows an attacker to inject iframes from any domain, bypassing the intended restrictions enforced by the allowediframes setting. This vulnerability is fixed in 3.2.5 and 3.3.0.beta5...