CVE intelligence and bounded remediation

CVE-2021-3899 — Canonical Apport security vulnerability

High CVSS 7.8

There is a race condition in the 'replaced executable' detection that, with the correct local configuration, allow an attacker to execute arbitrary code as root.

Severity
High
CVSS
7.8 (3.1)
Published
2024-06-03
CISA KEV
Not currently listed
Ecosystem
software/application
Weaknesses
CWE-367

Affected products

  • canonical / apport
  • canonical / ubuntu_linux / 18.04
  • canonical / ubuntu_linux / 20.04
  • canonical / ubuntu_linux / 21.10
  • canonical / ubuntu_linux / 22.04

Matched remediation archetype

Race condition, TOCTOU, and lifecycle synchronization

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Check exposure

  • Map concurrent actors, shared state, lock boundaries, signals, callbacks, retries, and check-then-use sequences in the affected path.
  • Determine whether untrusted users can influence timing, object names, filesystem state, or repeated state transitions.
  • Identify clustered and multi-process behavior that repository-local tests may not represent.

Remediate safely

  • Make the sensitive state transition atomic or protect it with a consistently ordered synchronization primitive.
  • Perform authorization and invariant checks on the same authoritative object and transaction used for the operation.
  • Use unique private resources, safe ownership transfer, and idempotent operations; add deterministic concurrency regression tests.

Authoritative sources

Complete CVE record and remediation plan

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