Hello dear maintainers, I also see this same error on my two Debian sid installs, please find at the end of this email the output of apt with suggested debug. The error happens on both external repos (docker, google chrome) and on debian ones.
My apt sources: deb https://deb.debian.org/debian/ sid main non-free non-free-firmware contrib deb-src https://deb.debian.org/debian/ sid main non-free non-free-firmware contrib deb https://ftp.fr.debian.org/debian/ experimental main non-free non-free-firmware contrib deb [arch=amd64] https://download.docker.com/linux/debian stretch stable deb [arch=amd64] http://dl.google.com/linux/chrome/deb/ stable main deb [arch=amd64] https://updates.signal.org/desktop/apt xenial main ==8<=====8<=====8<=====8<=== # apt update -o Debug::Acquire::gpgv=1 Ign:1 https://ftp.fr.debian.org/debian experimental InRelease Get:2 http://dl.google.com/linux/chrome/deb stable InRelease [1,825 B] 0% [Connected to debian.map.fastly.net (146.75.54.132)] [Connected to download.docker.com (18.239.236.67)] inside VerifyGetSigners Preparing to exec: /usr/bin/apt-key --quiet --readonly verify --status-fd 3 /tmp/apt.sig.emhK7K /tmp/apt.data.Q3Xxr4 Get:3 https://updates.signal.org/desktop/apt xenial InRelease [5,887 B] Get:4 https://deb.debian.org/debian sid InRelease [198 kB] Get:5 https://download.docker.com/linux/debian stretch InRelease [44.8 kB] 0% [5 InRelease 15.9 kB/44.8 kB 35%]gpgv exited with status 1 Summary: Good: Valid: Bad: Worthless: SoonWorthless: NoPubKey: Signed-By: NODATA: no Err:2 http://dl.google.com/linux/chrome/deb stable InRelease At least one invalid signature was encountered. 0% [5 InRelease 32.3 kB/44.8 kB 72%]inside VerifyGetSigners Preparing to exec: /usr/bin/apt-key --quiet --readonly verify --status-fd 3 /tmp/apt.sig.GxhUa7 /tmp/apt.data.THZQqW 0% [Working]gpgv exited with status 1 Summary: Good: Valid: Bad: Worthless: SoonWorthless: NoPubKey: Signed-By: NODATA: no Err:3 https://updates.signal.org/desktop/apt xenial InRelease At least one invalid signature was encountered. 0% [Working]inside VerifyGetSigners Preparing to exec: /usr/bin/apt-key --quiet --readonly verify --status-fd 3 /tmp/apt.sig.tW0Lmv /tmp/apt.data.GB4Nce gpgv exited with status 1 Summary: Good: Valid: Bad: Worthless: SoonWorthless: NoPubKey: Signed-By: NODATA: no Err:4 https://deb.debian.org/debian sid InRelease At least one invalid signature was encountered. 0% [Working]inside VerifyGetSigners Preparing to exec: /usr/bin/apt-key --quiet --readonly verify --status-fd 3 /tmp/apt.sig.fWMVK9 /tmp/apt.data.ZEJ1a3 gpgv exited with status 1 Summary: Good: Valid: Bad: Worthless: SoonWorthless: NoPubKey: Signed-By: NODATA: no Err:5 https://download.docker.com/linux/debian stretch InRelease At least one invalid signature was encountered. Ign:1 https://ftp.fr.debian.org/debian experimental InRelease Ign:1 https://ftp.fr.debian.org/debian experimental InRelease Err:1 https://ftp.fr.debian.org/debian experimental InRelease Could not connect to ftp.fr.debian.org:443 (212.27.32.66). - connect (111: Connection refused) Cannot initiate the connection to ftp.fr.debian.org:443 (2a01:e0c:1:1598::2). - connect (101: Network is unreachable) Warning: GPG error: http://dl.google.com/linux/chrome/deb stable InRelease: At least one invalid signature was encountered. Error: The repository 'http://dl.google.com/linux/chrome/deb stable InRelease' is not signed. Notice: Updating from such a repository can't be done securely, and is therefore disabled by default. Notice: See apt-secure(8) manpage for repository creation and user configuration details. Warning: GPG error: https://updates.signal.org/desktop/apt xenial InRelease: At least one invalid signature was encountered. Error: The repository 'https://updates.signal.org/desktop/apt xenial InRelease' is not signed. Notice: Updating from such a repository can't be done securely, and is therefore disabled by default. Notice: See apt-secure(8) manpage for repository creation and user configuration details. Warning: GPG error: https://deb.debian.org/debian sid InRelease: At least one invalid signature was encountered. Error: The repository 'https://deb.debian.org/debian sid InRelease' is not signed. Notice: Updating from such a repository can't be done securely, and is therefore disabled by default. Notice: See apt-secure(8) manpage for repository creation and user configuration details. Warning: GPG error: https://download.docker.com/linux/debian stretch InRelease: At least one invalid signature was encountered. Error: The repository 'https://download.docker.com/linux/debian stretch InRelease' is not signed. Notice: Updating from such a repository can't be done securely, and is therefore disabled by default. Notice: See apt-secure(8) manpage for repository creation and user configuration details.
