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

CVE-2020-14954 is fixed in 2 products on 1 platform, first by mutt 1.9.4-3ubuntu0.3, released June 21, 2020. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2020-14954
- Priority: Routine
- CVSS: n/a (Medium)
- EPSS: 0.0231
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jun 21, 2020

## 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."

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | mutt Ubuntu 18.04.6 LTS (bionic) | 1.9.4-3ubuntu0.3 | [mutt 1.9.4-3ubuntu0.3](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-mutt-1.9.4-3ubuntu0.3.md) | Jun 21, 2020 |
| Linux | mutt Ubuntu 20.04 LTS (focal) | 1.13.2-1ubuntu0.2 | [mutt 1.13.2-1ubuntu0.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-mutt-1.13.2-1ubuntu0.2.md) | Jun 21, 2020 |
| Linux | neomutt Ubuntu 18.04.6 LTS (bionic) | 20171215+dfsg.1-1ubuntu0.1~esm1 | [neomutt 20171215+dfsg.1-1ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-neomutt-20171215-dfsg.1-1ubuntu0.1-esm1.md) | Apr 14, 2022 |
| Linux | neomutt Ubuntu 20.04 LTS (focal) | 20191207+dfsg.1-1.1ubuntu0.1~esm1 | [neomutt 20191207+dfsg.1-1.1ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-neomutt-20191207-dfsg.1-1.1ubuntu0.1-esm1.md) | Nov 11, 2024 |

---

Data as of 2026-11-09T01:18:40Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

Free to use with attribution: show "Data: Patchblox Patch Radar" with a link to https://patchblox.com/security/patch-radar. Terms, including what needs a written agreement: https://patchblox.com/security/patch-radar/use-the-data

Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.