CVE-2025-9181
MediumCVSS 6.5Exploitation Probability (EPSS)
Low risk29th percentile - higher than 29% of all known CVEs
Summary
Uninitialized memory in the JavaScript Engine component. This vulnerability was fixed in Firefox 142, Firefox ESR 128.14, Firefox ESR 140.2, Thunderbird 142, Thunderbird 128.14, and Thunderbird 140.2.
Risk Assessment
Uninitialized memory may lead to data leakage or code execution, which could be exploited by an attacker to take control of the browser or email client. The risk is high as the vulnerability affects widely used applications.
Recommendation
Immediately update Firefox and Thunderbird to the latest versions (Firefox 142, Firefox ESR 128.14/140.2, Thunderbird 142/128.14/140.2). Enabling automatic updates is also recommended.
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Original NVD description (English source)
Uninitialized memory in the JavaScript Engine component. This vulnerability was fixed in Firefox 142, Firefox ESR 128.14, Firefox ESR 140.2, Thunderbird 142, Thunderbird 128.14, and Thunderbird 140.2.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS