CVE-2020-12387

HighCVSS 8.1/10Last modified Jun 17, 2026

Description

A race condition when running shutdown code for Web Worker led to a use-after-free vulnerability. This resulted in a potentially exploitable crash. This vulnerability affects Firefox ESR < 68.8, Firefox < 76, and Thunderbird < 68.8.0.

Metrics

CVSS 3.1 8.1/10CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Weakness enumeration

CWE-362CWE-416

Affected software

No affected versions have been published.

Timeline

Published
May 26, 2020
Last modified
Jun 17, 2026
NVD status
Modified

Related CVEs from 2020

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CVE-2020-12387: High severity, CVSS 8.1 | Vulnix