CVE-2026-12307

Modified Modified - Updated After Analysis

Memory Corruption Bug in Firefox

Publication date: 2026-06-16

Last updated on: 2026-06-18

Assigner: Mozilla Corporation

Description

Memory safety bug fixed in Firefox 152. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.

CVSS Scores

EPSS Scores

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Meta Information

Published

2026-06-16

Last Modified

2026-06-18

Generated

2026-07-06

AI Q&A

2026-06-16

EPSS Evaluated

2026-07-05

NVD

CVE-2026-12307

EUVD

EUVD-2026-37098

Affected Vendors & Products

Vendor	Product	Version / Range
mozilla	firefox	152
mozilla	firefox_esr	140.12

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-119	The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.

Attack-Flow Graph

Executive Summary

This vulnerability is a memory safety bug that was present in Mozilla Firefox. It was addressed and fixed in Firefox version 152 and Firefox ESR 140.12.

Mitigation Strategies

The vulnerability is fixed in Firefox 152 and Firefox ESR 140.12. To mitigate this vulnerability, you should update your Firefox browser to version 152 or later, or Firefox ESR to version 140.12 or later.

Impact Analysis

This vulnerability is a memory safety bug that was fixed in Thunderbird 152 and related versions. Memory safety bugs can potentially lead to crashes, data corruption, or exploitation by attackers to execute arbitrary code or cause denial of service.

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