Owncloud Ubuntu repository weak encryption

reported_bug
9.1.x
help

#1

While running apt-get update command, I got the following notice

W: http://download.owncloud.org/download/repositories/stable/Ubuntu_16.04/Release.gpg: Signature by key DDA2C105C4B73A6649AD2BBD47AE7F72479BC94B uses weak digest algorithm (SHA1)

Steps to reproduce
1. Make sure owncloud repository is added in your sources.
2. Run sudo apt-get update

Expected behaviour
The update should give no notice whatsoever.

Actual behaviour
Get the above error notice.

Server configuration
Operating system: Ubuntu 16.04
Web server: Apache
Database: MySQL
PHP version: 7.0
ownCloud version (see ownCloud admin page): 9.1.1
Updated from an older ownCloud or fresh install: 9.1.0


http://.../Ubuntu_16.04/Release.gpg: Signature by key uses weak digest algorithm (SHA1)
#2

There is a longer issue about this on github:


#3