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."
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | mutt | 1.14.4-1 | — |
| Debian 14 | neomutt | 20200619+dfsg.1-1 | — |
| Debian 13 | mutt | 1.14.4-1 | — |
| Debian 13 | neomutt | 20200619+dfsg.1-1 | — |
| Debian 12 | mutt | 1.14.4-1 | — |
| Debian 12 | neomutt | 20200619+dfsg.1-1 | — |
| Debian 10 | mutt | 1.10.1-2.1+deb10u2 | DSA-4707-1 |
| Debian 10 | neomutt | 20180716+dfsg.1-1+deb10u1 | DSA-4708-1 |
| Debian 9 | mutt | 1.7.2-1+deb9u3 | DSA-4707-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 8 | mutt | 1.5.23-3+deb8u2 | DLA-2268-2, DLA-2268-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | mutt | 1.13.2-1ubuntu0.2 | USN-4403-1 |
| Ubuntu 18.04 LTS | mutt | 1.9.4-3ubuntu0.3 | USN-4403-1 |
| Ubuntu 16.04 LTS | mutt | 1.5.24-1ubuntu0.4 | USN-4403-1 |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 24.04 LTS | neomutt | 20231103+dfsg1-1ubuntu0.1~esm1 | USN-7204-1 |
| Ubuntu Pro 22.04 LTS | neomutt | 20211029+dfsg1-1ubuntu0.1~esm1 | USN-7204-1 |
| Ubuntu Pro 20.04 LTS | neomutt | 20191207+dfsg.1-1.1ubuntu0.1~esm1 | USN-7204-1 |
| Ubuntu Pro 18.04 LTS | neomutt | 20171215+dfsg.1-1ubuntu0.1~esm1 | USN-7204-1 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP2 | mutt | 1.10.1-3.8.1 | SUSE-SU-2020:1771-1 |
| SLES 15 SP1 | mutt | 1.10.1-3.8.1 | SUSE-SU-2020:1771-1 |
| SLES 15 | mutt | 1.10.1-3.8.1 | SUSE-SU-2020:1771-1 |
| SLES 12 SP5 | mutt | 1.10.1-55.11.1 | SUSE-SU-2020:1794-1 |
| SLES 12 SP4 | mutt | 1.10.1-55.11.1 | SUSE-SU-2020:1794-1 |
Show 17 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP3 | mutt | 1.10.1-55.11.1 | SUSE-SU-2020:1794-1 |
| SLES 12 SP2 | mutt | 1.10.1-55.11.1 | SUSE-SU-2020:1794-1 |
| SLES 11 SP4 | mutt | 1.5.17-42.51.1 | SUSE-SU-2020:14414-1 |
| SLES for SAP 15 | mutt | 1.10.1-3.8.1 | SUSE-SU-2020:1771-1 |
| SLES for SAP 12 SP5 | mutt | 1.10.1-55.11.1 | SUSE-SU-2020:1794-1 |
| SLES for SAP 12 SP4 | mutt | 1.10.1-55.11.1 | SUSE-SU-2020:1794-1 |
| SLES for SAP 12 SP3 | mutt | 1.10.1-55.11.1 | SUSE-SU-2020:1794-1 |
| SLES for SAP 12 SP2 | mutt | 1.10.1-55.11.1 | SUSE-SU-2020:1794-1 |
| SLE HPC 15 | mutt | 1.10.1-3.8.1 | SUSE-SU-2020:1771-1 |
| SUSE Package Hub 15 SP2 | neomutt | 20201120-bp152.2.3.1 | openSUSE-SU-2020:2158-1 |
| SUSE Package Hub 15 SP1 | neomutt | 20201120-bp151.3.3.1 | openSUSE-SU-2020:2157-1 |
| SUSE OpenStack Cloud Crowbar 8 | mutt | 1.10.1-55.11.1 | SUSE-SU-2020:1794-1 |
| SUSE OpenStack Cloud 8 | mutt | 1.10.1-55.11.1 | SUSE-SU-2020:1794-1 |
| SUSE OpenStack Cloud 7 | mutt | 1.10.1-55.11.1 | SUSE-SU-2020:1794-1 |
| SUSE Linux Enterprise Point of Sale 11 SP3 | mutt | 1.5.17-42.51.1 | SUSE-SU-2020:14414-1 |
| SUSE HPE Helion OpenStack 8 | mutt | 1.10.1-55.11.1 | SUSE-SU-2020:1794-1 |
| SUSE Enterprise Storage 5 | mutt | 1.10.1-55.11.1 | SUSE-SU-2020:1794-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | mutt | 2.0.7-2.2 | openSUSE-SU-2024:11069-1 |
| openSUSE Tumbleweed | neomutt | 20210205-3.3 | openSUSE-SU-2024:11079-1 |
| openSUSE Leap 15.2 | mutt | 1.10.1-lp152.3.3.1 | openSUSE-SU-2020:0915-1 |
| openSUSE Leap 15.2 | neomutt | 20201120-lp152.2.3.1 | openSUSE-SU-2020:2127-1 |
| openSUSE Leap 15.1 | mutt | 1.10.1-lp151.2.3.1 | openSUSE-SU-2020:0903-1 |
| openSUSE Leap 15.1 | neomutt | 20201120-lp152.2.3.1 | openSUSE-SU-2020:2127-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2 | mutt | 5:1.5.21-29.amzn2.0.1 | ALAS2-2022-1892 |
Advisories 18
- USN-7204-1 neomutt vulnerabilities Ubuntu Security Notices (USN) · Apr 27, 2026
- DSA-4707-1 mutt - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-4708-1 neomutt - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-2268-1 mutt - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-2268-2 mutt - regression update Debian Security (DSA / DLA) · Mar 9, 2026
- USN-4403-1 mutt vulnerability and regression Ubuntu Security Notices (USN) · Feb 10, 2026
- openSUSE-SU-2020:2158-1 Security update for neomutt SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:1794-1 Security update for mutt SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:11069-1 mutt-2.0.7-2.2 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:14414-1 Security update for mutt SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:1771-1 Security update for mutt SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2020:2157-1 Security update for neomutt SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2020:0903-1 Security update for mutt SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2020:2127-1 Security update for neomutt SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:11079-1 neomutt-20210205-3.3 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2020:0915-1 Security update for mutt SUSE / openSUSE Security Updates · May 7, 2025
- WID-SEC-2022-2243 mutt: Schwachstelle ermöglicht Manipulation von Daten BSI CERT-Bund (WID) · Jan 15, 2025
- ALAS2-2022-1892 Moderate: mutt security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Dec 6, 2022
References
- DSA-4707 vendor-advisory
- 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
- DSA-4708 vendor-advisory
- openSUSE-SU-2020:0903 vendor-advisory
- openSUSE-SU-2020:0915 vendor-advisory
- [debian-lts-announce] 20200630 [SECURITY] [DLA 2268-1] mutt security update mailing-list
- [debian-lts-announce] 20200630 [SECURITY] [DLA 2268-2] mutt regression update mailing-list
- FEDORA-2020-1cb4c3697b vendor-advisory
- USN-4403-1 vendor-advisory
- FEDORA-2020-31af2ac7fd vendor-advisory
- GLSA-202007-57 vendor-advisory