# CVE-2019-11708: Mozilla Firefox and Thunderbird Sandbox Escape Vulnerability

Source: https://junglewise.ai/threats/cve-2019-11708-mozilla-firefox-and-thunderbird-sandbox-escape-vulnerability  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2022-05-23. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-2019-11708 · Severity: critical · CVSS 10 · Exploited in the wild · Published 2022-05-23

Insufficient vetting of parameters in the Prompt:Open IPC message between child and parent processes allows a compromised child process to force the non-sandboxed parent process to open arbitrary web content. When chained with other vulnerabilities, this enables a sandbox escape and remote code execution on the host system.

Technologies: [Mozilla Firefox](https://junglewise.ai/threats/technologies/firefox), [Mozilla Thunderbird](https://junglewise.ai/threats/technologies/thunderbird). Vendors: [Mozilla](https://junglewise.ai/threats/vendors/mozilla).

## Quick answers

**Is CVE-2019-11708 exploited in the wild?** Yes. CVE-2019-11708 is known to be exploited in the wild, first recorded on 23 May 2022. Treat it as urgent.

**How severe is CVE-2019-11708?** Critical severity, with a CVSS score of 10, published 23 May 2022.

**Which products and versions are affected?** Mozilla Firefox < 67.0.4; Mozilla Firefox ESR < 60.7.2; Mozilla Thunderbird < 60.7.2.

**Is there a fix for CVE-2019-11708?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2019-11708 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2019-11708?** Check whether you run Mozilla Firefox or Mozilla Thunderbird. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Affected products

- Mozilla Firefox < 67.0.4
- Mozilla Firefox ESR < 60.7.2
- Mozilla Thunderbird < 60.7.2

## Timeline

- 2019-07-28: disclosed: Initial NVD analysis date
- 2022-05-23: kev added: Added to CISA Known Exploited Vulnerabilities Catalog
- 2022-05-23: advisory: NVD publication date
- 2019-12-09: other: Public exploit chain for Windows 64-bit reported

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