CVE-2026-12298

Modified Modified - Updated After Analysis

Memory Corruption Bug in Firefox

Publication date: 2026-06-16

Last updated on: 2026-06-30

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

Probability:
Percentile:

Meta Information

Published

2026-06-16

Last Modified

2026-06-30

Generated

2026-07-06

AI Q&A

2026-06-16

EPSS Evaluated

2026-07-05

NVD

CVE-2026-12298

EUVD

EUVD-2026-37089

Affected Vendors & Products

Vendor	Product	Version / Range
mozilla	firefox	to 152.0 (exc)
mozilla	firefox	From 140.0 (inc) to 140.12.0 (exc)
mozilla	thunderbird	to 152.0.0 (exc)
mozilla	thunderbird	From 140.0 (inc) to 140.12.0 (exc)

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-416	The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.
CWE-125	The product reads data past the end, or before the beginning, of the intended buffer.
CWE-843	The product allocates or initializes a resource such as a pointer, object, or variable using one type, but it later accesses that resource using a type that is incompatible with the original type.
CWE-787	The product writes data past the end, or before the beginning, of the intended buffer.

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

Impact Analysis

This vulnerability is a memory safety bug in Firefox that was fixed in Firefox 152 and Firefox ESR 140.12.

Memory safety bugs can potentially lead to crashes, data corruption, or exploitation by attackers to execute arbitrary code or cause denial of service.

Hi! I’m here to help you understand CVE-2026-12298. Ask me anything about the vulnerability, its impact, or mitigation strategies.

0/70