CVE-2020-8833 (GCVE-0-2020-8833)

Vulnerability from cvelistv5 – Published: 2020-04-22 21:15 – Updated: 2024-09-16 20:53
VLAI
Title
Apport race condition in crash report permissions
Summary
Time-of-check Time-of-use Race Condition vulnerability on crash report ownership change in Apport allows for a possible privilege escalation opportunity. If fs.protected_symlinks is disabled, this can be exploited between the os.open and os.chown calls when the Apport cron script clears out crash files of size 0. A symlink with the same name as the deleted file can then be created upon which chown will be called, changing the file owner to root. Fixed in versions 2.20.1-0ubuntu2.23, 2.20.9-0ubuntu7.14, 2.20.11-0ubuntu8.8 and 2.20.11-0ubuntu22.
Severity
5.6 (Medium)
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N
CWE
  • CWE-367 - Time-of-check Time-of-use (TOCTOU) Race Condition
Assigner
canonical CNA under the mitre root
CNA scorecard B 82/100 over 62 records in the last 180 days details
References
URL Tags
https://usn.ubuntu.com/4315-1/ x_refsource_CONFIRM
https://bugs.launchpad.net/ubuntu/+source/apport/… x_refsource_CONFIRM
https://usn.ubuntu.com/4315-2/ vendor-advisoryx_refsource_UBUNTU
Impacted products
Vendor Product Version CPE status
Canonical Apport Affected: 2.20.1 , < 2.20.1-0ubuntu2.23 (custom)
Affected: 2.20.9 , < 2.20.9-0ubuntu7.14 (custom)
Affected: 2.20.11 , < 2.20.11-0ubuntu8.8 (custom)
guessed Create a notification for this product.
Date Public
2020-04-02 00:00
Credits
Maximilien Bourgeteau
Show details on NVD website
To clipboard 

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