CVE-2025-0240
MediumCVSS 4.0Exploitation Probability (EPSS)
Elevated risk50th percentile - higher than 50% of all known CVEs
Summary
Parsing a JavaScript module as JSON could, under some circumstances, cause cross-compartment access, potentially leading to use-after-free. Fixed in Firefox 134, Firefox ESR 128.6, Thunderbird 134, and Thunderbird 128.6.
Risk Assessment
An attacker could exploit this to execute code or crash the browser, potentially compromising user security.
Recommendation
Update Firefox or Thunderbird to the latest version that includes the fix.
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Original NVD description (English source)
Parsing a JavaScript module as JSON could, under some circumstances, cause cross-compartment access, which may result in a use-after-free. This vulnerability was fixed in Firefox 134, Firefox ESR 128.6, Thunderbird 134, and Thunderbird 128.6.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS