CVE-2026-6777

Received Received - Intake

DNS Vulnerability in Firefox 150 Networking Component Fixed

Publication date: 2026-04-21

Last updated on: 2026-04-22

Assigner: Mozilla Corporation

Description

Other issue in the Networking: DNS component. This vulnerability was fixed in Firefox 150 and Thunderbird 150.

CVSS Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published

2026-04-21

Last Modified

2026-04-22

Generated

2026-07-06

AI Q&A

2026-04-21

EPSS Evaluated

2026-07-05

NVD

CVE-2026-6777

EUVD

EUVD-2026-24118

Affected Vendors & Products

Vendor	Product	Version / Range
mozilla	firefox	to 150.0 (exc)
mozilla	thunderbird	to 150.0 (exc)

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-20	The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.
CWE-352	The web application does not, or cannot, sufficiently verify whether a request was intentionally provided by the user who sent the request, which could have originated from an unauthorized actor.
CWE-400	The product does not properly control the allocation and maintenance of a limited resource.

Attack-Flow Graph

Executive Summary

This vulnerability is an issue in the Networking: DNS component of Mozilla Firefox. It was addressed and fixed in Firefox version 150.

Impact Analysis

This vulnerability affects the Networking: DNS component in Firefox and has a CVSS v3.1 base score of 5.3, indicating a medium severity. It can be exploited remotely without privileges or user interaction and impacts availability, potentially causing denial of service or disruption in network functionality.

Mitigation Strategies

To mitigate this vulnerability, update Firefox to version 150 or later where the issue has been fixed.

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