CVE-2020-8833

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.

Affected Software

VendorProductVersion RangeStatus
CanonicalApport2.20.1 < 2.20.1-0ubuntu2.23affected
CanonicalApport2.20.9 < 2.20.9-0ubuntu7.14affected
CanonicalApport2.20.11 < 2.20.11-0ubuntu8.8affected

Weaknesses

  • CWE-367: CWE-367 Time-of-check Time-of-use (TOCTOU) Race Condition

ADP Enrichment

CVE Program Container

Additional References

References