Package: systemd Version: 242-7 Severity: important Tags: security systemd generates a directory name under /var/log/journal with the /etc/machine-id value, which is confidential according to the machine-id(5) man page:
This ID uniquely identifies the host. It should be considered "confidential", and must not be exposed in untrusted environments, in particular on the network. If a stable unique identifier that is tied to the machine is needed for some application, the machine ID or any part of it must not be used directly. Instead the machine ID should be hashed with a cryptographic, keyed hash function, using a fixed, application-specific key. That way the ID will be properly unique, and derived in a constant way from the machine ID but there will be no way to retrieve the original machine ID from the application-specific one. The sd_id128_get_machine_app_specific(3) API provides an implementation of such an algorithm. This directory name is not directly exposed on the network, but most users do not know where it comes from and that it is confidential, so that it may end up on the net, e.g. in debugging exchanges and when asking for help. An example: https://forum.ubuntu-fr.org/viewtopic.php?pid=21992288#p21992288 As a consequence, the machine-id is also present in journalctl output, which may also end up on the net. BTW, the fact that this ID is available in a file, in particular word-readable, instead of an API to generate a hash, is a bad idea. -- Package-specific info: -- System Information: Debian Release: bullseye/sid APT prefers unstable-debug APT policy: (500, 'unstable-debug'), (500, 'stable-updates'), (500, 'unstable'), (500, 'testing'), (500, 'stable'), (1, 'experimental') Architecture: amd64 (x86_64) Foreign Architectures: i386 Kernel: Linux 5.3.0-1-amd64 (SMP w/12 CPU cores) Kernel taint flags: TAINT_PROPRIETARY_MODULE, TAINT_OOT_MODULE, TAINT_UNSIGNED_MODULE Locale: LANG=POSIX, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8), LANGUAGE=POSIX (charmap=UTF-8) Shell: /bin/sh linked to /bin/dash Init: systemd (via /run/systemd/system) LSM: AppArmor: enabled Versions of packages systemd depends on: ii adduser 3.118 ii libacl1 2.2.53-5 ii libapparmor1 2.13.3-5+b1 ii libaudit1 1:2.8.5-2 ii libblkid1 2.34-0.1 ii libc6 2.29-2 ii libcap2 1:2.25-2 ii libcryptsetup12 2:2.2.1-1 ii libgcrypt20 1.8.5-3 ii libgnutls30 3.6.9-5 ii libgpg-error0 1.36-7 ii libidn2-0 2.2.0-2 ii libip4tc2 1.8.3-2 ii libkmod2 26-3 ii liblz4-1 1.9.1-2 ii liblzma5 5.2.4-1+b1 ii libmount1 2.34-0.1 ii libpam0g 1.3.1-5 ii libpcre2-8-0 10.32-5+b1 ii libseccomp2 2.4.1-2 ii libselinux1 2.9-2+b2 ii libsystemd0 242-7 ii mount 2.34-0.1 ii util-linux 2.34-0.1 Versions of packages systemd recommends: ii dbus 1.12.16-2 ii libpam-systemd 242-7 Versions of packages systemd suggests: ii policykit-1 0.105-26 pn systemd-container <none> Versions of packages systemd is related to: pn dracut <none> ii initramfs-tools 0.135 ii udev 242-7 -- Configuration Files: /etc/systemd/journald.conf changed: [Journal] Storage=persistent /etc/systemd/system.conf changed: [Manager] DefaultTimeoutStopSec=20s -- no debconf information
