TOCTOU Race Condition in Yarn
Published Mar 15, 2020 · Updated Oct 23, 2026 · Also known as GHSA-hjxc-462x-x77j
Original summary
Normalized public record · Updated Oct 23, 2026
TOCTOU Race Condition in Yarn
Publisher and source text is retained separately from QFinch interpretation.
QFinch assessment
The package integrity validation in yarn < 1.19.0 contains a TOCTOU vulnerability where the hash is computed before writing a package to cache. It's not computed again when reading from the cache. This may lead to a cache pollution attack. This issue is fixed in 1.19.0.
Evidence: public source recordsAffected products
| Affected package, product or range | Fix status |
|---|---|
| Consult the referenced vendor advisory for affected versions. | Consult source advisory |
Matching a version is only one part of assessing exposure. QFinch has not assessed your environment on this public page.
Remediation
Apply the vendor-supported fixed release or mitigation, then verify the affected component is no longer reachable.
- Confirm the affected product and reachable code path exist in your environment.
- Apply the vendor-supported patch or mitigation from the primary advisory.
- Rescan the exact deployed revision and retain verification evidence.
Evidence coverage
- SSVC priority
- LOW
- Confidence
- Not available
- Aliases
- GHSA-hjxc-462x-x77j
Scores appear only when corresponding evidence exists. Missing data is never interpreted as zero risk.
Sources and record history
Record history
Published Mar 15, 2020 · Last refreshed Oct 23, 2026