CVE-2020-10174

Description

init_tmp in TeeJee.FileSystem.vala in Timeshift before 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.

Weakness classification

• CWE-59: Improper Link Resolution Before File Access ('Link Following')
• CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

Primary references

• cve@mitre.org — Mailing List, Third Party Advisory
• cve@mitre.org — Issue Tracking, Third Party Advisory
• cve@mitre.org — Patch, Third Party Advisory
• cve@mitre.org — Release Notes, Third Party Advisory
• cve@mitre.org
• cve@mitre.org
• cve@mitre.org
• cve@mitre.org — Third Party Advisory
• af854a3a-2127-422b-91ae-364da2661108 — Mailing List, Third Party Advisory
• af854a3a-2127-422b-91ae-364da2661108 — Issue Tracking, Third Party Advisory
• af854a3a-2127-422b-91ae-364da2661108 — Patch, Third Party Advisory
• af854a3a-2127-422b-91ae-364da2661108 — Release Notes, Third Party Advisory