CVE-2026-12291
Received Received - Intake
Use-after-free in Firefox Networking HTTP Component

Publication date: 2026-06-16

Last updated on: 2026-06-16

Assigner: Mozilla Corporation

Description
Use-after-free in the Networking: HTTP component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, and Firefox ESR 115.37.
CVSS Scores
EPSS Scores
Probability:
Percentile:
Meta Information
Published
2026-06-16
Last Modified
2026-06-16
Generated
2026-06-16
AI Q&A
2026-06-16
EPSS Evaluated
N/A
NVD
CVE-2026-12291
EUVD
EUVD-2026-37082
Affected Vendors & Products
Showing 3 associated CPEs
Vendor Product Version / Range
mozilla firefox 152
mozilla firefox_esr 140.12
mozilla firefox_esr 115.37
Helpful Resources
Exploitability
CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-UNKNOWN
Attack-Flow Graph
AI Quick Actions
Instant insights powered by AI
Executive Summary

This vulnerability is a use-after-free issue in the Networking: HTTP component of Mozilla Firefox. A use-after-free vulnerability occurs when a program continues to use a pointer after the memory it points to has been freed, which can lead to unexpected behavior or security issues.

The issue was addressed and fixed in Firefox version 152, Firefox ESR 140.12, and Firefox ESR 115.37.

Mitigation Strategies

To mitigate this use-after-free vulnerability in the Networking: HTTP component, update Firefox to version 152 or later, or Firefox ESR to version 140.12 or later, or Firefox ESR 115.37 or later.

Impact Analysis

This vulnerability is a use-after-free issue in the Networking: HTTP component of Firefox. Such vulnerabilities can potentially allow attackers to execute arbitrary code, cause crashes, or lead to other unexpected behavior when using affected versions of Firefox.

It was fixed in Firefox 152, Firefox ESR 140.12, and Firefox ESR 115.37, so using versions prior to these may expose you to risk.

Chat Assistant
Ask questions about this CVE
Hi! I’m here to help you understand CVE-2026-12291. Ask me anything about the vulnerability, its impact, or mitigation strategies.
0/70
EPSS Chart