Memory Safety Bug in Firefox Browser by Mozilla
CVE-2026-12306

Currently unrated

Key Information:

Vendor: Mozilla
Status: Firefox
Vendor: CVE Published:; 16 June 2026

What is CVE-2026-12306?

A memory safety issue was identified in Mozilla's Firefox browser, leading to potential security risks for users. This vulnerability, now resolved in Firefox 152 and Firefox ESR 140.12, highlights the importance of keeping browser software updated. Users are encouraged to apply the latest patches to ensure their web experience remains secure and free from exploitation.

Affected Version(s)

Firefox 140.12

Firefox 152

References

https://bugzilla.mozilla.org/show_bug.cgi?id=2037323

https://www.mozilla.org/security/advisories/mfsa2026-57/

https://www.mozilla.org/security/advisories/mfsa2026-58/

Download the Critical Vulnerability Management Cheat Sheet

Timeline

Vulnerability published
Jun 16, 2026
Vulnerability Reserved
Jun 15, 2026

Credit

Mihalis Haatainen

CVE-2026-12306 Data

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