Description
An issue was discovered in the POP3 component of Courier Mail Server before 1.1.5. Meddler-in-the-middle attackers can pipeline commands after the POP3 STLS command, injecting plaintext commands into an encrypted user session.
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 | courier | 1.3.13-1 | — |
| Debian 13 | courier | 1.3.13-1 | — |
| Debian 12 | courier | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | courier | No fix yet | — |
| Ubuntu 26.04 LTS | courier | No fix yet | — |
| Ubuntu 25.10 | courier | No fix yet | — |
| Ubuntu 22.04 LTS | courier | No fix yet | — |
| Ubuntu 20.04 LTS | courier | No fix yet | — |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | courier | No fix yet | — |
| Ubuntu 16.04 LTS | courier | No fix yet | — |