Same-Origin Policy Bypass in Firefox from Mozilla

CVE-2026-100809

What is CVE-2026-100809?

A serious vulnerability exists in the DevTools component of Firefox, allowing attackers to bypass the same-origin policy. This could result in unauthorized access to sensitive data, enabling potential exploitation of the affected system. The vulnerability has been addressed in versions Firefox ESR 153.4 and Firefox 157, emphasizing the importance of updating to the latest releases to mitigate security risks. Users are urged to remain vigilant and apply necessary updates promptly.

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