CVE-2019-9815

If hyperthreading is not disabled, a timing attack vulnerability exists, similar to previous Spectre attacks. Apple has shipped macOS 10.14.5 with an option to disable hyperthreading in applications running untrusted code in a thread through a new sysctl. Firefox now makes use of it on the main thread and any worker threads. *Note: users need to update to macOS 10.14.5 in order to take advantage of this change.*. This vulnerability affects Thunderbird < 60.7, Firefox < 67, and Firefox ESR < 60.7.

• CWE-203

• https://bugzilla.mozilla.org/show_bug.cgi?id=1546544Permissions Required, Third Party Advisory
• https://mdsattacks.com/Third Party Advisory
• https://www.mozilla.org/security/advisories/mfsa2019-13/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2019-14/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2019-15/Vendor Advisory
• https://bugzilla.mozilla.org/show_bug.cgi?id=1546544Permissions Required, Third Party Advisory
• https://mdsattacks.com/Third Party Advisory
• https://www.mozilla.org/security/advisories/mfsa2019-13/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2019-14/Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2019-15/Vendor Advisory

Published

Jul 23, 2019

Last Modified

Jun 17, 2026

Status

Modified

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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