How severe is CVE-2019-11708?

CVE-2019-11708 has a CVSS score of 10/10, rated CRITICAL. Immediate patching is strongly recommended.

Which packages are affected by CVE-2019-11708?

Affected package information for CVE-2019-11708 is not yet fully mapped. Check the official advisory links for details.

How do I fix CVE-2019-11708?

No fixed version has been published for CVE-2019-11708 yet. Monitor the advisory for updates, apply mitigations recommended by the vendor, and use O3 Security to track when a fix becomes available in your stack.

Is CVE-2019-11708 actively exploited in the wild?

Yes. There are 5 known exploit references for CVE-2019-11708, including 1 documented proof-of-concept exploit on Exploit-DB and 3 in-the-wild exploitations observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for CVE-2019-11708?

CVE-2019-11708 has an EPSS (Exploit Prediction Scoring System) score of 68.8%, placing it in the 99th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. A score above 50% indicates significantly elevated exploitation risk — immediate patching is strongly recommended.

Is CVE-2019-11708 in the CISA Known Exploited Vulnerabilities catalog?

Yes. CVE-2019-11708 (Mozilla Firefox and Thunderbird Sandbox Escape Vulnerability) was added to CISA's Known Exploited Vulnerabilities (KEV) catalog on 2022-05-23. CISA required all US federal civilian agencies to remediate this vulnerability by 2022-06-13. The required action was: Apply updates per vendor instructions. Being listed in the KEV catalog is the strongest possible confirmation of active exploitation — treat this as a critical priority.

When was CVE-2019-11708 published, and has it been updated?

CVE-2019-11708 was published on July 23, 2019 and was last updated on April 16, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

CVE-2019-11708: Remote Code Execution (Critical 10)

EPSS Exploitation Probability

via FIRST.org ↗

68.8%probability of exploitation in next 30 days

High Risk99th percentile0.00%

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Description

Insufficient vetting of parameters passed with the Prompt:Open IPC message between child and parent processes can result in the non-sandboxed parent process opening web content chosen by a compromised child process. When combined with additional vulnerabilities this could result in executing arbitrary code on the user's computer. This vulnerability affects Firefox ESR < 60.7.2, Firefox < 67.0.4, and Thunderbird < 60.7.2.

Frequently Asked Questions

Insufficient vetting of parameters passed with the Prompt:Open IPC message between child and parent processes can result in the non-sandboxed parent process opening web content chosen by a compromised child process. When combined with additional vulnerabilities this could result in executing arbitrary code on the user's computer. This vulnerability affects Firefox ESR < 60.7.2, Firefox < 67.0.4, and Thunderbird < 60.7.2.

O3 Security · Impact-Aware SCA

Is CVE-2019-11708 in your stack?

O3 detects CVE-2019-11708 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

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