Description
An issue was discovered in Enigmail before 1.9.9. Signature spoofing is possible because the UI does not properly distinguish between an attachment signature, and a signature that applies to the entire containing message, aka TBE-01-021. This is demonstrated by an e-mail message with an attachment that is a signed e-mail message in message/rfc822 format.
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 | 2:1.9.9-1 | — |
| Debian 9 | enigmail | 2:1.9.9-1~deb9u1 | DSA-4070-1 |
| Debian 8 | enigmail | 2:1.9.9-1~deb8u1 | DSA-4070-1 |
| Debian 7 | enigmail | 2:1.9.9-1~deb7u1 | DLA-1219-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | enigmail | 2:1.9.9-0ubuntu0.16.04.1 | — |
| Ubuntu 14.04 LTS | enigmail | 2:1.9.9-0ubuntu0.14.04.1 | — |
Advisories 2
- DSA-4070-1 enigmail - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-1219-1 enigmail - security update Debian Security (DSA / DLA) · Mar 9, 2026
References
- https://enigmail.net/download/other/Enigmail%20Pentest%20Report%20by%20Cure53%20-%20Excerpt.pdf
- https://sourceforge.net/p/enigmail/bugs/709/
- https://lists.debian.org/debian-security-announce/2017/msg00333.html
- https://www.mail-archive.com/enigmail-users%40enigmail.net/msg04280.html
- [debian-lts-announce] 20171223 [SECURITY] [DLA 1219-1] enigmail security update mailing-list
- DSA-4070 vendor-advisory