# CVE-2023-32677: Users who can send invitations can erroneously add users to streams during invitation in Zulip

> Users with invitation permissions can bypass stream addition restrictions to add new users to streams they shouldn't control.

- **Severity:** Low 3.1 (`CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 19 May 2023
- **Updated:** 12 Feb 2025
- **Also known as:** GHSA-mrvp-96q6-jpvc

## What is CVE-2023-32677?

CVE-2023-32677 is a low-severity missing authorization vulnerability in zulip, published on 19 May 2023. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Zulip is an open-source team collaboration tool with unique topic-based threading. Zulip administrators can configure Zulip to limit who can add users to streams, and separately to limit who can invite users to the organization. In Zulip Server 6.1 and below, the UI which allows a user to invite a new user also allows them to set the streams that the new user is invited to -- even if the inviting user would not have permissions to add an existing user to streams. While such a configuration is likely rare in practice, the behavior does violate security-related controls. This does not let a user invite new users to streams they cannot see, or would not be able to add users to if they had that general permission. This issue has been addressed in version 6.2. Users are advised to upgrade. Users unable to upgrade may limit sending of invitations down to users who also have the permission to add users to streams.

Weakness: CWE-862 (Missing Authorization)

## Which versions are affected by CVE-2023-32677?

It affects 1 product.


Products: Zulip Zulip.

## How do I fix CVE-2023-32677?

No fix has been published for CVE-2023-32677 yet. Limit exposure of the affected software until one is available.

## Is CVE-2023-32677 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2023-32677 exists.

## Other vulnerabilities in zulip

- [CVE-2021-43799](https://insights.sbomify.com/CVE-2021-43799/): RabbitMQ exposes ports with weak default secrets in Zulip Server (high 8.6)
- [CVE-2022-35962](https://insights.sbomify.com/CVE-2022-35962/): Crafted link in Zulip message can cause disclosure of credentials (high 8.0)
- [CVE-2016-4427](https://insights.sbomify.com/CVE-2016-4427/): Auth bypass in zulip (high 7.5)
- [CVE-2021-3866](https://insights.sbomify.com/CVE-2021-3866/): Cross-site Scripting (XSS) - Stored in zulip/zulip (medium 6.8)
- [CVE-2023-28623](https://insights.sbomify.com/CVE-2023-28623/): Unauthorized user can register an account in specific configurations in Zulip (medium 6.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-32677 and fix it if it is affected.

What it is: CVE-2023-32677 is a low-severity missing authorization vulnerability in zulip, published on 19 May 2023. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2023-32677 exists.

Affected product: zulip. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2023-32677/ (Markdown: https://insights.sbomify.com/CVE-2023-32677/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-32677
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-32677
- OSV: https://osv.dev/vulnerability/CVE-2023-32677

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-32677/
Summaries are generated and may contain mistakes; the official description above is the record.