CVE-2019-9813

8.8 HIGH

Published: April 26, 2019 Modified: November 25, 2025

Description

Incorrect handling of __proto__ mutations may lead to type confusion in IonMonkey JIT code and can be leveraged for arbitrary memory read and write. This vulnerability affects Firefox < 66.0.1, Firefox ESR < 60.6.1, and Thunderbird < 60.6.1.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0

Vector String

CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory

https://access.redhat.com/errata/RHSA-2019:0966

Source: security@mozilla.org

https://access.redhat.com/errata/RHSA-2019:1144

Source: security@mozilla.org

https://bugzilla.mozilla.org/show_bug.cgi?id=1538006

Source: security@mozilla.org

Issue Tracking Permissions Required Vendor Advisory

https://www.mozilla.org/security/advisories/mfsa2019-09/

Source: security@mozilla.org

Vendor Advisory

https://www.mozilla.org/security/advisories/mfsa2019-10/

Source: security@mozilla.org

Vendor Advisory

https://www.mozilla.org/security/advisories/mfsa2019-12/

Source: security@mozilla.org

Vendor Advisory

https://access.redhat.com/errata/RHSA-2019:0966