init_tmp in TeeJee.FileSystem.vala in Timeshift prior to 20.03 unsafely reuses a preexisting temporary directory in the predictable location /tmp/timeshift. It follows symlinks in this location or uses directories owned by unprivileged users. Because Timeshift also executes scripts under this location, an attacker can attempt to win a race condition to replace scripts created by Timeshift with attacker-controlled scripts. Upon success, an attacker-controlled script is executed with full root privileges. This logic is practically always triggered when Timeshift runs regardless of the command-line arguments used.
| Vulnerable Product | Search on Vulmon | Subscribe to Product |
|---|---|---|
timeshift project timeshift |
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fedoraproject fedora 30 |
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fedoraproject fedora 31 |
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fedoraproject fedora 32 |
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canonical ubuntu linux 19.10 |
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