Description
An issue was discovered in KDE KMail before 19.12.3. By using the proprietary (non-RFC6068) "mailto?attach=..." parameter, a website (or other source of mailto links) can make KMail attach local files to a composed email message without showing a warning to the user, as demonstrated by an attach=.bash_history value.
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 | kmail | 4:20.04.1-1 | — |
| Debian 13 | kmail | 4:20.04.1-1 | — |
| Debian 12 | kmail | 4:20.04.1-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 20.04 LTS | kmail | 4:19.12.3-0ubuntu1+esm1 | USN-7731-1 |
| Ubuntu Pro 18.04 LTS | kmail | 4:17.12.3-0ubuntu1+esm1 | USN-7731-1 |
| Ubuntu Pro 16.04 LTS | kdepim | 4:15.12.3-0ubuntu1.1+esm1 | USN-7729-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 14.04 LTS | kdepim | 4:4.13.3-0ubuntu0.2+esm1 | USN-7729-1 |
Advisories 3
- USN-7729-1 kdepim vulnerabilities Ubuntu Security Notices (USN) · Jun 25, 2026
- USN-7731-1 kmail vulnerabilities Ubuntu Security Notices (USN) · Feb 10, 2026
- WID-SEC-2025-1951 Kmail: Schwachstelle ermöglicht Offenlegung von Informationen BSI CERT-Bund (WID) · Sep 3, 2025