Actively exploited in the wild
Mozilla Firefox and Thunderbird Type Confusion Vulnerability
Mozilla - Firefox and Thunderbird · Listed in the CISA KEV since 2022-05-23. This indicates confirmed attacks in production environments.
Required action: Apply updates per vendor instructions.
CVE-2019-11707
HighCVSS 8.8KEVSummary
A type confusion vulnerability in the JavaScript engine of Firefox and Thunderbird, caused by issues with Array.pop, can lead to an exploitable crash. Targeted attacks in the wild are known.
Risk Assessment
An attacker could remotely crash the browser or potentially execute arbitrary code, posing a serious risk to users.
Recommendation
Immediately update Firefox and Thunderbird to patched versions.
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Original NVD description (English source)
A type confusion vulnerability can occur when manipulating JavaScript objects due to issues in Array.pop. This can allow for an exploitable crash. We are aware of targeted attacks in the wild abusing this flaw. This vulnerability affects Firefox ESR < 60.7.1, Firefox < 67.0.3, and Thunderbird < 60.7.2.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS