I agree on this key needing to be available in the/an official Ubuntu keyring package.
For now, because the original key file is not even accessible via HTTPS, I am attaching a copy of it here. The file is dated 2016-07-04 16:10, and has the following SHA{256,512} hashes: 4a54623d5ec01d098441a42413d5d176c3292113aed9d274ac18ddaec50b76ce dbgsym-release-key.asc 728caec72fa2062f6d931a2c231433ee7dd0181d10d59ac6ec2afe90abc4cf17e3c9a7a4e82430ffdbd850eb68557bd33c1882e7de1dd93bc9b8dbbc61119f82 dbgsym-release-key.asc Original location: http://ddebs.ubuntu.com/dbgsym-release-key.asc If anyone sees a difference with the original, please speak up. ** Attachment added: "dbgsym-release-key.asc" https://bugs.launchpad.net/ubuntu/+source/ubuntu-keyring/+bug/643623/+attachment/4903350/+files/dbgsym-release-key.asc -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to ubuntu-keyring in Ubuntu. https://bugs.launchpad.net/bugs/643623 Title: Should ubuntu-keyring include the debug archive key? Status in ubuntu-keyring package in Ubuntu: Confirmed Bug description: Binary package hint: ubuntu-keyring Currently there doesn't seem to be a good way for developers who haven't been to many keysignings to establish trust in the Ubuntu Debug Symbol Archive Automatic Signing Key (428D7C01) SIgning this key with with Ubuntu Archive Automatic Signing Key (or equivalent) and/or including the Ubuntu Debug Symbol Archive Automatic Signing Key in ubuntu-keyring could help to solve this problem. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubuntu-keyring/+bug/643623/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp