Hello Mikko, thanks for the report; I believe that's working as intended, those bytes are part of the DER encoding; there's an excellent answer at https://crypto.stackexchange.com/a/19982/1400 that describes the meanings of each of those bytes.
Thanks ** Information type changed from Private Security to Public Security ** Changed in: gcr (Ubuntu) Status: New => Invalid -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to gcr in Ubuntu. https://bugs.launchpad.net/bugs/1969118 Title: Certificate viewer shows extra bytes for RSA keys Status in gcr package in Ubuntu: Invalid Bug description: When I view a x509 certificate using gcr-viewer .../path/to/certificate.pem and open the "Details" section and check the RSA public key information, the section that lists the public key renders extra 8 bytes at the start and 5 bytes at the end which are not actually part of the key. I haven't tried if this happens with other file types except x509, or with encryption methods except RSA. The exact certificate I viewed can be downloaded from https://crt.sh/?d=6454583403 and the expected public key modulus should start with 00:b6:28:0b:44:... but the certificate viewer shows public key starting with bytes 30 82 01 0A 02 82 01 01 00 B6 28 0B 44. Note the extra bytes 30 82 01 0A 02 82 01 01. The extra bytes seem to be static and do not change after re-lanching the viewer again. There are also extra bytes in the end of the displayed key. I'm marking this bug as a security vulnerability for now because (1) This tool is supposed to used to check encryption credentials, and (2) It's still unknown if this is some kind of 8 byte underflow/5 byte overflow or just a rendering problem. I'm not aware of the viewer writing extra bytes to any memory location so I would assume this is just a rendering issue. I'm fine with this issue being public so feel free to publish at your discretion. ProblemType: Bug DistroRelease: Ubuntu 18.04 Package: gcr 3.28.0-1 ProcVersionSignature: Ubuntu 5.4.0-107.121~18.04.1-lowlatency 5.4.174 Uname: Linux 5.4.0-107-lowlatency x86_64 ApportVersion: 2.20.9-0ubuntu7.27 Architecture: amd64 CurrentDesktop: MATE Date: Thu Apr 14 15:47:18 2022 EcryptfsInUse: Yes InstallationDate: Installed on 2019-01-05 (1194 days ago) InstallationMedia: Ubuntu 18.04.1 LTS "Bionic Beaver" - Release amd64 (20180725) SourcePackage: gcr UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gcr/+bug/1969118/+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