Discourse

Discourse is a platform for community discussion. A malicious admin could use this vulnerability to perform port enumeration on the local host or other hosts on the internal network, as well as against hosts on the Internet. Latest `stable`, `beta`, and `test-passed` versions are now patched. As a workaround, self-hosters can use `DISCOURSE_BLOCKED_IP_BLOCKS` env var (which overrides `blocked_ip_blocks` setting) to stop webhooks from accessing private IPs.Show less

Discourse Patreon enables syncronization between Discourse Groups and Patreon rewards. On sites with Patreon login enabled, an improper authentication vulnerability could be used to take control of a victim's forum account. This vulnerability is patched in commit number 846d012151514b35ce42a1636c7d70f6dcee879e of the discourse-patreon plugin. Out of an abundance of caution, any Discourse accounts which have logged in with an unverified-email Patreon account will be logged out and asked to verify their email address on their next login. As a workaround, disable the patreon integration and log out all users with associated Patreon accounts.Show less

discourse-chat is a plugin for the Discourse message board which adds chat functionality. In versions prior to 0.9 some places render a chat channel's name and description in an unsafe way, allowing staff members to cause an cross site scripting (XSS) attack by inserting unsafe HTML into them. Version 0.9 has addressed this issue. Users are advised to upgrade. There are no known workarounds for this issue.Show less

DiscoTOC is a Discourse theme component that generates a table of contents for topics. Users that can create topics in TOC-enabled categories (and have sufficient trust level - configured in component's settings) are able to inject arbitrary HTML on that topic's page. The issue has been fixed on the `main` branch. Admins can update the theme component through the admin UI (Customize -> Themes -> Components -> DiscoTOC -> Check for Updates). Alternatively, admins can temporarily disable the DiscoTOC theme component.Show less

Discourse is an open source discussion platform. Starting with version 2.9.0.beta5 and prior to version 2.9.0.beta10, an incomplete quote can generate a JavaScript error which will crash the current page in the browser in some cases. Version 2.9.0.beta10 added a fix and tests to ensure incomplete quotes won't break the app. As a workaround, the quote can be fixed via the rails console.Show less

Discourse is an open source discussion platform. In versions prior to 2.8.9 on the `stable` branch and prior to 2.9.0.beta10 on the `beta` and `tests-passed` branches, a malicious actor can add large payloads of text into the Location and Website fields of a user profile, which causes issues for other users when loading that profile. A fix to limit the length of user input for these fields is included in version 2.8.9 on the `stable` branch and version 2.9.0.beta10 on the `beta` and `tests-passed` branches. There are no known workarounds.Show less

Discourse is an open source discussion platform. In versions prior to 2.8.9 on the `stable` branch and prior to 2.9.0.beta10 on the `beta` and `tests-passed` branches, a moderator can create new and edit existing themes by using the API when they should not be able to do so. The problem is patched in version 2.8.9 on the `stable` branch and version 2.9.0.beta10 on the `beta` and `tests-passed` branches. There are no known workarounds.Show less

Discourse is an open source discussion platform. In versions prior to 2.8.9 on the `stable` branch and prior to 2.9.0.beta10 on the `beta` and `tests-passed` branches, admins can upload a maliciously crafted Zip or Gzip Tar archive to write files at arbitrary locations and trigger remote code execution. The problem is patched in version 2.8.9 on the `stable` branch and version 2.9.0.beta10 on the `beta` and `tests-passed` branches. There are no known workarounds.Show less

Discourse-Chat is an asynchronous messaging plugin for the Discourse open-source discussion platform. Users of Discourse Chat can be affected by admin users inserting HTML into chat titles and descriptions, causing a Cross-Site Scripting (XSS) attack. Version 0.9 contains a patch for this issue.Show less

Discourse is the an open source discussion platform. In affected versions an email activation route can be abused to send mass spam emails. A fix has been included in the latest stable, beta and tests-passed versions of Discourse which rate limits emails. Users are advised to upgrade. Users unable to upgrade should manually rate limit email.Show less

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 tests-passed versions of Discourse. Users are advised to upgrade. There are no known workarounds for this vulnerability.Show less

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 has been configured to add the user that accepts the invite into restricted groups. Once a user has been incorrectly added to a restricted group, the user may then be able to view content which that are restricted to the respective group. Users are advised to upgrade to the current stable releases. There are no known workarounds to this issue.Show less

discourse-chat is a chat plugin for the Discourse application. Versions prior to 0.4 are vulnerable to an exposure of sensitive information, where an attacker who knows the message ID for a channel they do not have access to can view that message using the chat message lookup endpoint, primarily affecting direct message channels. There are no known workarounds for this issue, and users are advised to update the plugin.Show less

Discourse is an open-source discussion platform. Prior to version 2.8.4 in the `stable` branch and version `2.9.0.beta5` in the `beta` and `tests-passed` branches, banner topic data is exposed on login-required sites. This issue is patched in version 2.8.4 in the `stable` branch and version `2.9.0.beta5` in the `beta` and `tests-passed` branches of Discourse. As a workaround, one may disable banners.Show less

Discourse Calendar is a calendar plugin for Discourse, an open-source messaging app. Prior to version 1.0.1, parsing and rendering of Event names can be susceptible to cross-site scripting (XSS) attacks. This vulnerability only affects sites which have modified or disabled Discourse’s default Content Security Policy. This issue is patched in version 1.0.1 of the Discourse Calendar plugin. As a workaround, ensure that the Content Security Policy is enabled, and has not been modified in a way which would make it more vulnerable to XSS attacks.Show less

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 `must_approve_users` check and invites by staff are always approved automatically. The issue is patched in Discourse version 2.8.4 on the `stable` branch and version `2.9.0.beta5` on the `beta` and `tests-passed` branches. As a workaround, disable invites or increase `min_trust_level_to_allow_invite` to reduce the attack surface to more trusted users.Show less

Discourse Assign is a plugin for assigning users to a topic in Discourse, an open-source messaging platform. Prior to version 1.0.1, the UserBookmarkSerializer serialized the whole User / Group object, which leaked some private information. The data was only being serialized to people who could view assignment info, which is limited to staff by default. For the vast majority of sites, this data was only leaked to trusted staff member, but for sites with assign features enabled publicly, the data was accessible to more people than just staff. Version 1.0.1 contains a patch. There are currently no known workarounds.Show less

Discourse is an open source platform for community discussion. A category's group permissions settings can be viewed by anyone that has access to the category. As a result, a normal user is able to see whether a group has read/write permissions in the category even though the information should only be available to the users that can manage a category. This issue is patched in the latest stable, beta and tests-passed versions of Discourse. There are no workarounds for this problem.Show less

Discourse is an open source platform for community discussion. In affected versions an attacker can poison the cache for anonymous (i.e. not logged in) users, such that the users are shown the crawler view of the site instead of the HTML page. This can lead to a partial denial-of-service. This issue is patched in the latest stable, beta and tests-passed versions of Discourse. There are no known workarounds for this issue.Show less