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.
https://www.mozilla.org/security/advisories/mfsa2020-17/
https://www.mozilla.org/security/advisories/mfsa2020-18/
https://www.mozilla.org/security/advisories/mfsa2020-16/
https://bugzilla.mozilla.org/show_bug.cgi?id=1545345
https://usn.ubuntu.com/4373-1/
Source: MITRE
Published: 2020-05-26
Updated: 2021-12-14
Type: CWE-362
Base Score: 6.8
Vector: AV:N/AC:M/Au:N/C:P/I:P/A:P
Impact Score: 6.4
Exploitability Score: 8.6
Severity: MEDIUM
Base Score: 8.1
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Impact Score: 5.9
Exploitability Score: 2.2
Severity: HIGH