# CVE-2019-9812: Firefox ESR: Given a compromised sandboxed content process due to a separate vulnerability, it is possible to escape…

CVE-2019-9812 is fixed in 4 products on 2 platforms, first by firefox 69.0+build2-0ubuntu0.18.04.1, released September 3, 2019. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2019-9812
- Priority: High
- CVSS: 9.3 (Important)
- EPSS: 0.0151
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Sep 3, 2019
- Vendor advisory: https://nvd.nist.gov/vuln/detail/CVE-2019-9812

## Description

Given a compromised sandboxed content process due to a separate vulnerability, it is possible to escape that sandbox by loading accounts.firefox.com in that process and forcing a log-in to a malicious Firefox Sync account. Preference settings that disable the sandbox are then synchronized to the local machine and the compromised browser would restart without the sandbox if a crash is triggered. This vulnerability affects Firefox ESR < 60.9, Firefox ESR < 68.1, and Firefox < 69.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Windows apps | Mozilla Firefox ESR (en-US) | 78.0esr | [Mozilla Firefox ESR (en-US) 78.0esr](https://patchblox.com/security/data/fix/windows-app/mozilla.firefox.esr-78.0esr.md) | Jun 25, 2020 |
| Linux | firefox RHEL 8 | 0:68.1.0-1.el8_0 | [RHSA-2019:2663](https://patchblox.com/security/data/fix/linux/rhsa-2019-2663.md) | Sep 4, 2019 |
| Linux | firefox Ubuntu 18.04.6 LTS (bionic) | 69.0+build2-0ubuntu0.18.04.1 | [firefox 69.0+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-69.0-build2-0ubuntu0.18.04.1.md) | Sep 3, 2019 |
| Linux | firefox ol 8 | 0:68.1.0-1.0.1.el8_0 | [ELSA-2019-2663](https://patchblox.com/security/data/fix/linux/elsa-2019-2663.md) | Sep 6, 2019 |
| Linux | firefox-geckodriver Ubuntu 18.04.6 LTS (bionic) | 69.0+build2-0ubuntu0.18.04.1 | [firefox-geckodriver 69.0+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-geckodriver-69.0-build2-0ubuntu0.18.04.1.md) | Sep 3, 2019 |
| Linux | firefox-mozsymbols Ubuntu 18.04.6 LTS (bionic) | 69.0+build2-0ubuntu0.18.04.1 | [firefox-mozsymbols 69.0+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-mozsymbols-69.0-build2-0ubuntu0.18.04.1.md) | Sep 3, 2019 |

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