CVE intelligence and bounded remediation

CVE-2019-17021 — Mozilla Firefox security vulnerability

Medium CVSS 5.3

During the initialization of a new content process, a race condition occurs that can allow a content process to disclose heap addresses from the parent process. *Note: this issue only occurs on Windows. Other operating systems are unaffected.*. This vulnerability affects Firefox ESR < 68.4 and Firefox < 72.

Severity
Medium
CVSS
5.3 (3.1)
Published
2020-01-08
CISA KEV
Not currently listed
Ecosystem
browser
Weaknesses
CWE-362

Affected products

  • mozilla / firefox
  • mozilla / firefox_esr
  • opensuse / leap / 15.1

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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