Bug 432040

Summary: OpenPGP/Mime Signatures with umlauts in the from address are invalid
Product: [Applications] kmail2 Reporter: Stefan Dösinger <stefandoesinger>
Component: cryptoAssignee: kdepim bugs <pim-bugs-null>
Status: RESOLVED DUPLICATE    
Severity: normal CC: sknauss
Priority: NOR    
Version First Reported In: 5.15.3   
Target Milestone: ---   
Platform: Gentoo Packages   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:
Attachments: Example email with bad signature

Description Stefan Dösinger 2021-01-24 15:55:46 UTC 
Created attachment 135131 [details]
Example email with bad signature

When creating an email signed with a PGP key but without encrypting it the resulting signature is invalid. Kmail itself reports the signature as invalid. Other mail clients (Thunderbird, Apple mail + gpgtools for Mac) agree. Kmail correctly verifies OpenPGP/MIME signatures from other clients.

A workaround is to use inline-openpgp. Emails that are encrypted in addition to being signed are unaffected.


STEPS TO REPRODUCE
1. Set up an email identity with a PGP public+private key
2. Draft an email to yourself. Disable encryption but keep signing on
3. Store the email in the outbox - sending is not necessary
4. Open the email in the outbox folder


OBSERVED RESULT
Kmail reports that it cannot verify the email because of an unknown encryption key. However, other email clients will report that the signature is not valid.

EXPECTED RESULT
The email is correctly signed

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: 
(available in About System)
KDE Plasma Version: 5.20.5
KDE Frameworks Version: 5.77.0
Qt Version: 5.15.2
Kernel 5.10.10-gentoo

ADDITIONAL INFORMATION

The PGP public key my example email is signed with: http://keys.gnupg.net/pks/lookup?op=get&search=0x8CB81F9A72BBA155
Comment 1 Stefan Dösinger 2021-01-24 16:10:47 UTC 
An update: The problem seems to be tied to the umlaut in my name:

From: Stefan =?ISO-8859-1?Q?D=F6singer?= <stefandoesinger@gmx.at>

Changing my profile name to "Doesinger" results in a working signature. I can put umlauts in the mail body just fine.
Comment 2 Sandro Knauß 2021-02-22 00:21:23 UTC 

*** This bug has been marked as a duplicate of bug 427091 ***