Name: CVE-2019-9821: Concurrent Execution using Shared Resource with Improper Synchronization
Creator: Rapid7
Published: 2019-07-23T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2019-9821, CWE-362, CWE-416, CVSS 8.1, EPSS 0.00846

A use-after-free vulnerability can occur in AssertWorkerThread due to a race condition with shared workers. This results in a potentially exploitable crash. This vulnerability affects Firefox < 67.

CVSS Details

CVSS 3.1 Base Score: 8.1
CVSS 3.0 Vector: (CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Arch Linux	—	Upgrade to the latest version of Arch Linux	Jul 11, 2025	Jul 23, 2019
Freebsd	—	Upgrade seamonkeyUpgrade linux-seamonkeyUpgrade thunderbirdUpgrade firefox-esrUpgrade firefoxUpgrade linux-firefoxUpgrade libxulUpgrade linux-thunderbirdUpgrade waterfox	May 23, 2019	May 22, 2019
Mfsa2019 13	—	Upgrade to Mozilla Firefox version 67.0Upgrade to the latest version of Mozilla Firefox	May 22, 2019	May 21, 2019
Suse	—	Upgrade MozillaFirefoxUpgrade MozillaFirefox-translations-commonUpgrade MozillaFirefox-develUpgrade mozillafirefox-buildsymbolsUpgrade MozillaFirefox-translations-otherUpgrade mozillafirefox-branding-upstream	Jun 10, 2019	May 21, 2019
Ubuntu	—	Upgrade firefox	May 22, 2019	May 21, 2019

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CVSS Details

Covered by Rapid7

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