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CVE-2020-8833
Apport race condition in crash report permissions
Medium5.6EPSS 0.34%
- Published
- Updated
- Reserved
- Assigned by
- canonical
Description
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.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| canonicalCNA (assigner) | 3.1 | Medium5.6 | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N |
| NVDNVD · Modified | 3.1 | Medium4.7 | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N |
- EPSS (exploitation in 30 days)
- 0.34% · top 72% of all CVEs (7 Nov 2026)
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The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.6.
Weakness
Affected products
References (3)
- https://usn.ubuntu.com/4315-1/ (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://bugs.launchpad.net/ubuntu/+source/apport/+bug/1862933 (opens in a new tab)x_refsource_CONFIRMx_transferred
- USN-4315-2 (opens in a new tab)vendor-advisoryx_refsource_UBUNTUx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
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[](https://trackcve.app/cve/CVE-2020-8833)Record last updated .