GPG verification failed with debian 12 channel synchronization

SUSE Multi Linux Server 5.0.5

The synchronization of Debian 12 channels failed due to Debian changing the the GPG signature:

2025/08/09 04:48:39 +02:00 Command: ['/usr/bin/spacewalk-repo-sync', '--channel', 'debian-12-main-updates-amd64', '--type', 'deb', '--non-interactive']
2025/08/09 04:48:39 +02:00 Sync of channel started.
2025/08/09 04:48:39 +02:00 Repo URL: http://deb.debian.org/debian/dists/bookworm-updates/main/binary-amd64/
::::
2025/08/10 04:48:59 - spacewalk.common.repo - Repo has no valid GPG signature.
2025/08/10 04:48:59 +02:00 Plugin error: GPG verification failed: http://deb.debian.org/debian/dists/bookworm-updates/InRelease

Engineering is working on adding the Debian 13 key to the default keyring which will then resolve this issue. In the interim it is required to add the GPG key manually:

From MLM host:
# cd /tmp
 
Download the Debian 13 archive signing key
# wget https://ftp-master.debian.org/keys/archive-key-13-security.asc 
# wget https://ftp-master.debian.org/keys/archive-key-13.asc
 
Import the key to the MLM server
# mgradm gpg add archive-key-13-security.asc 
# mgradm gpg add archive-key-13.asc
 
Verify keys are imported
# rpm -qa gpg-pubkey* --qf "%{NAME}-%{VERSION}-%{RELEASE}\n"
 
Retry to synchronize the channel again:
# mgrctl exec -it "spacewalk-repo-sync -c debian-12-main-updates-amd64"

GPG signature was changed by Debian.

If the message "gpg: public key of ultimately trusted key 4363305A16ED677E not found" is encountered when adding the key on the MLM host, rebuild the inconsistent trust database:

# gpg --update-trustdb

 Then try to add the key again.