Vulnerability in Apport Project
CVE-2020-8833
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.
Vulnerability class: TOCTOU (Time-of-Check to Time-of-Use)
EPSS: 0.003 (27.2th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 5.6 (Medium). Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N.
Affected products
- Apport_project Apport
- Canonical Apport — versions 2.20.1, 2.20.9, 2.20.11
- Canonical Ubuntu_linux — versions 14.04, 16.04, 18.04
Weakness classification (CWE)
Public proof-of-concept exploits
References
- security@ubuntu.com (x_refsource_CONFIRM, Third Party Advisory)
- security@ubuntu.com (x_refsource_CONFIRM, Exploit, Third Party Advisory)
- security@ubuntu.com (x_refsource_UBUNTU, vendor-advisory, Third Party Advisory)
Frequently asked questions
- What is CVE-2020-8833?
- CVE-2020-8833 is a medium-severity vulnerability in Apport Project, classified under Time-of-check Time-of-use (TOCTOU) Race Condition. CVSS score: 5.6/10. Published 2020-04-22.
- How severe is CVE-2020-8833?
- Medium severity. CVSS v3 base score is 5.6 out of 10.
- Is CVE-2020-8833 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.