View Issue Details

IDProjectCategoryView StatusLast Update
0005376SOGoWeb Mailpublic2021-08-23 15:16
Reporteredward.johns Assigned Tofrancis  
Status resolvedResolutionfixed 
PlatformServerOSLinux UbuntuOS Version20.04.2 LTS
Product Version5.1.1 
Fixed in Version5.3.0 
Summary0005376: Web Mail is not honoring RFC-821 line lengths with identity signature blocks, resulting in invalid S/MIME digital signtures

RFC-821 specifies a maximum line length of 1000 characters. When using an HTML signature in SOGo, the HTML source is put into a single line. In my case, the line is over 1000 characters. When the message is digitally signed using S/MIME, SOGo saves the email in the IMAP sent folder. The digital signature there is correct, because the non-compliant line is not truncated. However, the sent email lines are truncated to 1000 characters by the SMTP server (postfix, in my case). When delivered, the message has an extra line break, invalidating the signature.

Steps To Reproduce

Requires a valid S/MIME certificate configured for the account.

Go to "Preferences", "Mail", and set "Compose messages in" to HTML.
Go to "IMAP Accounts", and select the pencil icon to edit preferences.
Under "Identities", "Signature", select "View Source"
Repeat copying the following text to the Signature field until it is longer than 1000 characters: <span>.</span>
Select OK.
Select the Disk icon to save preferences.
Compose an email to your email address.
Under Security, ensure that Sign is checked.
Enter Test in the Subject and message body)
Send the message.
Select the message in the sent folder. It says "Message is signed"
Select the message in the Inbox. It says "Digital Signature is not valid"

Additional Information

A possible solution is to restrict the signature block HTML source to 1000 characters, and keep existing line breaks in the HTML, rather than collapsing the source as it is currently implemented.

TagsNo tags attached.




2021-08-10 18:14

reporter   ~0015416

When I said, "A possible solution is to restrict the signature block HTML source to 1000 characters", I meant that "A possible solution is to restrict each line of the signature block HTML source to 1000 characters"

Related Changesets

sogo: master 6cf3d991

2021-08-23 11:08


Details Diff
fix(mail): encode text MIME parts in quoted-printable

This will limit each line to a maximum of 70 characters.

Fixes 0005376
Affected Issues
mod - SoObjects/Mailer/SOGoDraftObject.m Diff File

Issue History

Date Modified Username Field Change
2021-08-10 17:48 edward.johns New Issue
2021-08-10 18:14 edward.johns Note Added: 0015416
2021-08-23 15:16 francis Changeset attached => sogo master 6cf3d991
2021-08-23 15:16 francis Assigned To => francis
2021-08-23 15:16 francis Resolution open => fixed
2021-08-23 15:16 francis Status new => resolved
2021-08-23 15:16 francis Fixed in Version => 5.3.0