deepin-clone before 1.1.3 uses a fixed path /tmp/repo.iso in the BootDoctor::fix() function to download an ISO file, and follows symlinks there. An unprivileged user can prepare a symlink attack there to create or overwrite files in arbitrary file system locations. The content is not attacker controlled. By winning a race condition to replace the /tmp/repo.iso symlink by an attacker controlled ISO file, further privilege escalation may be possible.
Publication date: Thu, 04 Jul 2019 17:15:00 +0000