Zulip Server Security Vulnerabilities

CVE-2017-0881

An error in the implementation of an autosubscribe feature in the check_stream_exists route of the Zulip group chat application server before 1.4.3 allowed an authenticated user to subscribe to a private stream that should have required an invitation from an existing member to join. The issue affec...

CVE-2017-0896

Zulip Server 1.5.1 and below suffer from an error in the implementation of the invite_by_admins_only setting in the Zulip group chat application server that allowed an authenticated user to invite other users to join a Zulip organization even if the organization was configured to prevent this.

CVE-2017-0910

In Zulip Server before 1.7.1, on a server with multiple realms, a vulnerability in the invitation system lets an authorized user of one realm on the server create a user account on any other realm.

CVE-2018-9986

In Zulip Server versions before 1.7.2, there were XSS issues with the frontend markdown processor.

CVE-2018-9987

In Zulip Server versions 1.5.x, 1.6.x, and 1.7.x before 1.7.2, there was an XSS issue with muting notifications.

CVE-2018-9990

In Zulip Server versions before 1.7.2, there was an XSS issue with stream names in topic typeahead.

CVE-2018-9999

In Zulip Server versions before 1.7.2, there was an XSS issue with user uploads and the (default) LOCAL_UPLOADS_DIR storage backend.

CVE-2019-16215

The Markdown parser in Zulip server before 2.0.5 used a regular expression vulnerable to exponential backtracking. A user who is logged into the server could send a crafted message causing the server to spend an effectively arbitrary amount of CPU time and stall the processing of future messages.

CVE-2019-16216

Zulip server before 2.0.5 incompletely validated the MIME types of uploaded files. A user who is logged into the server could upload files of certain types to mount a stored cross-site scripting attack on other logged-in users. On a Zulip server using the default local uploads backend, the attack i...

CVE-2019-18933

In Zulip Server versions from 1.7.0 to before 2.0.7, a bug in the new user signup process meant that users who registered their account using social authentication (e.g., GitHub or Google SSO) in an organization that also allows password authentication could have their personal API key stolen by an...

CVE-2019-19775

The image thumbnailing handler in Zulip Server versions 1.9.0 to before 2.0.8 allowed an open redirect that was visible to logged-in users.

CVE-2020-10935

Zulip Server before 2.1.3 allows XSS via a Markdown link, with resultant account takeover.

CVE-2020-12759

Zulip Server before 2.1.5 allows reflected XSS via the Dropbox webhook.

CVE-2020-14194

Zulip Server before 2.1.5 allows reverse tabnapping via a topic header link.

CVE-2020-14215

Zulip Server before 2.1.5 has Incorrect Access Control because 0198_preregistrationuser_invited_as adds the administrator role to invitations.

CVE-2020-15070

Zulip Server 2.x before 2.1.7 allows eval injection if a privileged attacker were able to write directly to the postgres database, and chose to write a crafted custom profile field value.

CVE-2020-9444

Zulip Server before 2.1.3 allows reverse tabnabbing via the Markdown functionality.

CVE-2020-9445

Zulip Server before 2.1.3 allows XSS via the modal_link feature in the Markdown functionality.

CVE-2021-30477

An issue was discovered in Zulip Server before 3.4. A bug in the implementation of replies to messages sent by outgoing webhooks to private streams meant that an outgoing webhook bot could be used to send messages to private streams that the user was not intended to be able to send messages to.

CVE-2021-30478

An issue was discovered in Zulip Server before 3.4. A bug in the implementation of the can_forge_sender permission (previously is_api_super_user) resulted in users with this permission being able to send messages appearing as if sent by a system bot, including to other organizations hosted by the s...

CVE-2021-30479

An issue was discovered in Zulip Server before 3.4. A bug in the implementation of the all_public_streams API feature resulted in guest users being able to receive message traffic to public streams that should have been only accessible to members of the organization.

CVE-2021-30487

In the topic moving API in Zulip Server 3.x before 3.4, organization administrators were able to move messages to streams in other organizations hosted by the same Zulip installation.

CVE-2022-21706

Zulip is an open-source team collaboration tool with topic-based threading. Zulip Server version 2.0.0 and above are vulnerable to insufficient access control with multi-use invitations. A Zulip Server deployment which hosts multiple organizations is vulnerable to an attack where an invitation crea...

CVE-2022-23656

Zulip is an open source team chat app. The main development branch of Zulip Server from June 2021 and later is vulnerable to a cross-site scripting vulnerability on the recent topics page. An attacker could maliciously craft a full name for their account and send messages to a topic with several pa...

CVE-2022-31134

Zulip is an open-source team collaboration tool. Zulip Server versions 2.1.0 above have a user interface tool, accessible only to server owners and server administrators, which provides a way to download a "public data" export. While this export is only accessible to administrators, in many configu...

CVE-2022-41914

Zulip is an open-source team collaboration tool. For organizations with System for Cross-domain Identity Management(SCIM) account management enabled, Zulip Server 5.0 through 5.6 checked the SCIM bearer token using a comparator that did not run in constant time. Therefore, it might theoretically be...

CVE-2023-22735

Zulip is an open-source team collaboration tool. In versions of zulip prior to commit 2f6c5a8 but after commit 04cf68b users could upload files with arbitrary Content-Type which would be served from the Zulip hostname with Content-Disposition: inline and no Content-Security-Policy header, allowing ...

CVE-2023-32678

Zulip is an open-source team collaboration tool with topic-based threading that combines email and chat. Users who used to be subscribed to a private stream and have been removed from it since retain the ability to edit messages/topics, move messages to other streams, and delete messages that they ...

CVE-2023-33186

Zulip is an open-source team collaboration tool with unique topic-based threading that combines the best of email and chat to make remote work productive and delightful. The main development branch of Zulip Server from May 2, 2023 and later, including beta versions 7.0-beta1 and 7.0-beta2, is vulne...

CVE-2023-47642

Zulip is an open-source team collaboration tool. It was discovered by the Zulip development team that active users who had previously been subscribed to a stream incorrectly continued being able to use the Zulip API to access metadata for that stream. As a result, users who had been removed from a ...

CVE-2024-21630

Zulip is an open-source team collaboration tool. A vulnerability in version 8.0 is similar to CVE-2023-32677, but applies to multi-use invitations, not single-use invitation links as in the prior CVE. Specifically, it applies when the installation has configured non-admins to be able to invite user...