Description
The signature verification routine in Enigmail before 2.0.7 interprets user ids as status/control messages and does not correctly keep track of the status of multiple signatures, which allows remote attackers to spoof arbitrary email signatures via public keys containing crafted primary user ids.
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 11 | enigmail | 2:2.0.7-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 22.04 LTS | enigmail | No fix yet | — |
| Ubuntu 20.04 LTS | enigmail | No fix yet | — |
| Ubuntu 18.04 LTS | enigmail | No fix yet | — |
| Ubuntu 16.04 LTS | enigmail | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 | enigmail | 2.0.7-3.7.2 | SUSE-SU-2018:2243-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | enigmail | 2.2.4-1.4 | openSUSE-SU-2024:10736-1 |
Advisories 2
- SUSE-SU-2018:2243-1 Security update for enigmail SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:10736-1 enigmail-2.2.4-1.4 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
References
- http://openwall.com/lists/oss-security/2018/06/13/10
- https://www.enigmail.net/index.php/en/download/changelog
- [oss-security] 20190430 Spoofing OpenPGP and S/MIME Signatures in Emails (multiple clients) mailing-list
- 20190430 OpenPGP and S/MIME signature forgery attacks in multiple email clients mailing-list
- http://packetstormsecurity.com/files/152703/Johnny-You-Are-Fired.html
- https://github.com/RUB-NDS/Johnny-You-Are-Fired
- https://github.com/RUB-NDS/Johnny-You-Are-Fired/blob/master/paper/johnny-fired.pdf