LTSP LDM through 2.18.06 allows fat-client root access because the LDM_USERNAME variable may have an empty value if the user's shell lacks support for Bourne shell syntax. This is related to a run-x-session script.Referenceshttps://git.launchpad.net/~ltsp-upstream/ltsp/+git/ldm/commit/?id=c351ac69ef63ed6c84221cef73e409059661b8bahttps://www.debian.org/security/2020/dsa-4601https://lists.debian.org/debian-lts-announce/2020/01/msg00007.html
