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Vendor

Discourse

323 known vulnerabilities.

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  • Low 2.0

    Discourse: Stored XSS in discourse-local-dates plugin

    Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, the discourse-local-dates plugin rendered crafted local-date format data as HTML on sites with a modified or disabled default Content Security Policy. This i…

  • Low 2.1

    Discourse has a subscription access bypass in its discourse-subscriptions plugin

    Discourse is an open-source discussion platform. In versions prior to 2026.1.4, 2026.3.1, 2026.4.1 and 2026.5.0-latest.1, a vulnerability in the discourse-subscriptions plugin allows users to gain access to subscription-gated groups without completing payment…

  • Low 2.7

    Discourse: Staged user custom fields are exposed on public invite pages

    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, staged user custom fields and username are exposed on public invite pages without em…

  • Low 2.1

    Discourse: Stored XSS via unescaped assignee name

    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, when the hidden prioritize_full_name_in_ux site setting is enabled (defaults to fals…

  • Low 2.0

    discourse-subscriptions plugin leaking stripe API key in multisite environment

    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, the discourse-subscriptions plugin leaks stripe API keys across sites in a multisite…

  • Low 2.7

    Discourse Authorization Page Displays Unvalidated Redirect Domain

    Discourse is an open-source discussion platform. Prior to versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2, an unauthenticated attacker can cause a legitimate Discourse authorization page to display an attacker-controlled domain, facilitating social enginee…

  • Low 3.5

    Discourse users can edit or synonymize hidden tags they can't see

    Discourse is an open-source discussion platform. Prior to versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2, users with tag-editing permissions could edit and create synonyms for tags hidden in restricted tag groups, even if they lacked visibility into those…

  • Low 1.3

    Discourse staff can modify any user's group notification level

    Discourse is an open-source discussion platform. Prior to versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2, staff can modify any user's group notification level. Versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 contain a patch. No known workarounds are av…

  • Low 3.5

    Discourse exposes ip_address of flagged user

    Discourse is an open-source discussion platform. Prior to versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2, the `ip_address` of a flagged user is exposed to any user who can access the review queue, including users who should not be able to see IP addresses…

  • Low 2.2

    Discourse has moderator privilege escalation via arbitrary post_id in suspend/silence endpoint

    Discourse is an open-source discussion platform. Versions prior to 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 allow a moderator to edit site policy documents (ToS, guidelines, privacy policy) that they are explicitly prohibited from modifying. Versions 2026.3.…

  • Low 2.2

    Discourse has Improper Authorization in "Post Edits" Report For Moderators

    Discourse is an open-source discussion platform. Prior to versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2, moderators were able to see the first 40 characters of post edits in PMs and private categories. Versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 c…

  • Low 2.7

    Discourse leaks PM post edits to moderators

    Discourse is an open-source discussion platform. Prior to versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2, the Post Edits admin report (/admin/reports/post_edits) leaked the first 40 characters of raw post content from private messages and secure categorie…

  • Low 2.3

    Discourse vulnerable to group membership addition permission bypass via discourse-policy plugin

    Discourse is an open-source discussion platform. Versions prior to 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 have a security flaw in the discourse-policy plugin which allowed a user with policy creation permission to gain membership access to any private/rest…

  • Low 1.2

    Discourse Vulnerable to Unauthorized Topic Creation in Staff-Only Categories via Topic Timer publish_to_category

    Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, TL4 users can publish topics into staff-only categories via the `publish_to_category` topic timer, bypassing authorization checks. Versions 2025.12.2, 2026.1…

  • Low 1.3

    Privilege Escalation via Mass Assignment Allows Regular Users to Set Topics as Global Banners

    Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, an improper authorization check in the topic management logic allows authenticated users to modify privileged attributes of their topics. By manipulating spe…

  • Low 1.3

    Discourse has XSS when editing a malicious post

    Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, a user full name can be evaluated as raw HTML when the following settings are set: `display_name_on_posts` => true; and `prioritize_username_in_ux` => false.…

  • Low 1.3

    Discourse doesn't prevent moderators from exporting user Chat DMs

    Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, moderators could export user Chat DMs via the CSV export endpoint by exploiting an overly permissive allowlist in `can_export_entity?`. The method allowed mo…

  • Low 1.3

    DIscourse has DM communication-preference bypass when adding members

    Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, DM communication-preference bypass when adding members via `Chat::AddUsersToChannel` — a user could add targets who have blocked/ignored/muted them to an exi…

  • Low 1.3

    Discourse doesn't validate destination topic when moving posts

    Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, the `move_posts` action only checked `can_move_posts?` on the source topic but never validated write permissions on the destination topic. This allowed TL4 u…

  • Low 1.3

    Discourse doesn't ensure guardian check when creating QueryGroupBookmark

    Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, missing `validate_before_create` authorization in Data Explorer's `QueryGroupBookmarkable` allows any logged-in user to create bookmarks for query groups the…

  • Low 3.5

    Discourse is vulnerable to XSS when quoting chat messages

    Discourse is an open-source community discussion platform. Versions 3.5.0 and below are vulnerable to XSS attacks through parsing and rendering of chat channel titles and chat thread titles via the quote message functionality when using the rich text editor. …

  • Low 2.4

    Discourse welcome banner user name XSS

    Discourse is an open-source discussion platform. Welcome banner user name string for logged in users can be vulnerable to XSS attacks, which affect the user themselves or an admin impersonating them. Admins can temporarily alter the welcome_banner.header.logg…

  • Low 3.5

    Discourse Policy plugin private group members visible

    Discourse Policy plugin gives the ability to confirm users have seen or done something. Prior to version 0.1.1, if there was a policy posted to a public topic that was tied to a private group then the group members could be shown to non-group members. This is…

  • Low 3.1

    Discourse Code Review Plugin vulnerable to XSS via auto link commits

    The Discourse Code Review Plugin allows users to review GitHub commits on Discourse. Prior to commit eed3a80, an attacker can execute arbitrary JavaScript on users' browsers by posting links to malicious GitHub commits. This problem is patched in commit eed3a…

  • Low 2.2

    Users can see other user's tagged PMs in Discourse

    Discourse is an open source platform for community discussion. PM titles and metadata can be read by other users when the "PM tags allowed for groups" option is enabled, the other user is a member of a group added to this option, and the PM has been tagged. T…

  • Low 3.1

    Client Side Path Traversal using activate account route in Discourse

    Discourse is an open source platform for community discussion. In affected versions an attacker can trick a target user to make changes to their own username via carefully crafted link using the `activate-account` route. This problem has been patched in the l…

  • Low 2.2

    Moderators can view Screened emails even when the “moderators view emails” option is disabled in Discourse

    Discourse is an open source platform for community discussion. Moderators can see the Screened emails list in the admin dashboard, and through that can learn the email of a user. This problem is patched in the latest version of Discourse. Users unable to upgr…

  • Low 2.4

    Discourse doesn't limit reviewable user serializer payload

    Discourse is an open-source discussion platform. Prior to version 3.2.3 on the `stable` branch and version 3.3.0.beta4 on the `beta` and `tests-passed` branches, moderators using the review queue to review users may see a users email address even when the All…

  • Low 3.1

    Discourse secure uploads accessible to guests even when login is required

    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.

  • Low 3.5

    Reaction data for user notifications exposed in Discourse-reactions

    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.

  • Low 3.4

    Discourse SSRF vulnerability in Embedding

    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, the embedding feature is susceptible to server side request forgery. The issue is p…

  • Low 3.3

    Unread bookmark reminder notifications that the user cannot access can be seen

    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, there is an edge case where a bookmark reminder is sent and an unread notification …

  • Low 3.7

    Exposure of poll options and votes to unauthorized users in Discourse

    Discourse is an open source platform for community discussion. Attackers with details specific to a poll in a topic can use the `/polls/grouped_poll_results` endpoint to view the content of options in the poll and the number of votes for groups of poll partic…

  • Low 2.6

    Discourse Race Condition in Accept Invite

    Discourse is an open source discussion platform. Prior to version 3.0.6 of the `stable` branch and version 3.1.0.beta7 of the `beta` and `tests-passed` branches, more users than permitted could be created from invite links. The issue is patched in version 3.0…

  • Low 3.5

    Topic Title Validation Skipped When Changing Category in Discourse

    Discourse is an open source discussion platform. When editing a topic, there is a vulnerability that enables a user to bypass the topic title validations for things like title length, number of emojis in title and blank topic titles. The issue is patched in t…

  • Low 3.1

    Discourse's canonical url not being used for topic embeddings

    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, multiple duplicate topics could be created if topic embedding is enabled. This issue is patched i…

  • Low 2.0

    Discourse's general category permissions could be set back to default

    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.…

  • Low 2.7

    Denial of service via admin theme import route in Discourse

    Discourse is an open source platform for community discussion. In affected versions a maliciously crafted request from a Discourse administrator can lead to a long-running request and eventual timeout. This has the greatest potential impact in shared hosting …

  • Low 3.5

    Presence of restricted personal Discourse messages may be leaked if tagged with a tag

    Discourse is an open-source messaging platform. In versions 3.0.1 and prior on the `stable` branch and versions 3.1.0.beta2 and prior on the `beta` and `tests-passed` branches, the count of personal messages displayed for a tag is a count of all personal mess…

  • Low 3.1

    Yearly Review Plugin leaking anonymised users data in discourse-yearly-review

    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…