CVE-2019-9812 Security feature bypass in Firefox

What is CVE-2019-9812?

CVE-2019-9812 is a critical vulnerability in Mozilla Firefox, published on 8 Jan 2020. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

Official 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.

Which versions are affected by CVE-2019-9812?

It affects 1 product.

Products include Mozilla Firefox.

How do I fix CVE-2019-9812?

Upgrade to a fixed version.

Is CVE-2019-9812 being exploited?

There is no known exploitation of CVE-2019-9812 in the wild and no public exploit code.

Other vulnerabilities in Mozilla Firefox

• CVE-2019-11708 Mozilla Firefox and Thunderbird Sandbox Escape Exploited Critical 10.0
• CVE-2010-3765 Mozilla Multiple Products Remote Code Execution Exploited Critical 9.8
• CVE-2022-26486 Mozilla Firefox Use-After-Free Exploited Critical 9.6
• CVE-2022-26485 Mozilla Firefox Use-After-Free Exploited High 8.8
• CVE-2019-11707 Mozilla Firefox and Thunderbird Type Confusion Exploited High 8.8

All Mozilla Firefox vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2019-9812, GHSA-jh9w-r6qf-jxc5, UBUNTU-CVE-2019-9812.