CVE-2026-4700
Modified
Modified - Updated After Analysis
Mitigation Bypass in Firefox HTTP Networking Component
Vulnerability report for CVE-2026-4700, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-03-24
Last updated on: 2026-06-30
Assigner: Mozilla Corporation
Description
Description
Mitigation bypass in the Networking: HTTP component. This vulnerability was fixed in Firefox 149, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.
CVSS Scores
EPSS Scores
| Probability: | |
| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| mozilla | firefox | to 149.0 (exc) |
| mozilla | firefox | to 140.9.0 (exc) |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-444 | The product acts as an intermediary HTTP agent (such as a proxy or firewall) in the data flow between two entities such as a client and server, but it does not interpret malformed HTTP requests or responses in ways that are consistent with how the messages will be processed by those entities that are at the ultimate destination. |
| CWE-288 | The product requires authentication, but the product has an alternate path or channel that does not require authentication. |
