CVE-2025-1934
MediumCVSS 6.5Exploitation Probability (EPSS)
Low risk37th percentile - higher than 37% of all known CVEs
Summary
The vulnerability allowed interrupting RegExp processing and running additional JavaScript, potentially triggering garbage collection when the engine was not expecting it. Fixed in Firefox 136, Firefox ESR 128.8, Thunderbird 136, and Thunderbird 128.8.
Risk Assessment
An attacker could exploit this to execute unauthorized code in the browser or mail client, potentially leading to data compromise or system takeover.
Recommendation
Update Firefox and Thunderbird to the patched versions immediately.
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- CVE-2026-109740Critical
Sandbox escape due to incorrect boundary conditions in the Widget: Win32 component. The flaw was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.
Original NVD description (English source)
It was possible to interrupt the processing of a RegExp bailout and run additional JavaScript, potentially triggering garbage collection when the engine was not expecting it. This vulnerability was fixed in Firefox 136, Firefox ESR 128.8, Thunderbird 136, and Thunderbird 128.8.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS