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CVE-2019-9815
If hyperthreading is not disabled, a timing attack vulnerability exists, similar to previous Spectre attacks. Apple has shipped macOS…
High8.1EPSS 1.8%
- Published
- Updated
- Reserved
- Assigned by
- mozilla
Description
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.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.0 | High8.1 | CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 1.8% · top 21% of all CVEs (6 Nov 2026)
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The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.1.
Weakness
- Disable hyperthreading on content JavaScript threads on macOS
- CWE-203 (opens in a new tab)All about CWE-203 and its CVEs
Affected products
- affected unspecified – < 60.7
- affected unspecified – < 67
- affected unspecified – < 60.7
References (5)
- https://www.mozilla.org/security/advisories/mfsa2019-13/ (opens in a new tab)x_refsource_MISCx_transferred
- https://www.mozilla.org/security/advisories/mfsa2019-15/ (opens in a new tab)x_refsource_MISCx_transferred
- https://www.mozilla.org/security/advisories/mfsa2019-14/ (opens in a new tab)x_refsource_MISCx_transferred
- https://bugzilla.mozilla.org/show_bug.cgi?id=1546544 (opens in a new tab)x_refsource_MISCx_transferred
- https://mdsattacks.com/ (opens in a new tab)x_refsource_MISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2019-9815)Record last updated .