CVE-2026-2791: Mitigation bypass in the Networking: Cache component

Published Feb 24, 2026
·
Updated

Mitigation bypass in the Networking: Cache component. This vulnerability affects Firefox < 148 and Firefox ESR < 140.8.

Other sources

Mitigation bypass in the Networking: Cache component. This vulnerability was fixed in Firefox 148, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.

— MITRE

Affected Software

8 affected componentsFixes available
Mozilla Firefox<148
148
Mozilla Firefox ESR<140.8
140.8
Mozilla Thunderbird<148
148
Mozilla Thunderbird<140.8
140.8
Mozilla Firefox<140.8.0
Mozilla Firefox<148.0
Mozilla Thunderbird<140.8.0
Mozilla Thunderbird<148.0

Event History

Feb 24, 2026
CVE Published
via Mozilla·12:00 AM
Data Sourced
via Mozilla·12:00 AM
DescriptionSeverityAffected Software
Updated
via Mozilla·12:00 AM
Affected Software
CVE Published
via MITRE·01:33 PM
Data Sourced
via MITRE·01:33 PM
Description
Data Sourced
via Red Hat·02:06 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·02:16 PM
DescriptionSeverityWeaknessAffected Software
Jan 4, 58137
Event
via FIRST·05:23 PM

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

Free Weekly Intel

Don't miss critical vulnerabilities

Join thousands of security professionals who receive our weekly digest of trending CVEs, zero-days, and exploited vulnerabilities.

No spam. Unsubscribe anytime.

Frequently Asked Questions

1

What is the severity of CVE-2026-2791?

CVE-2026-2791 has been classified as a high severity vulnerability due to the potential for a mitigation bypass in the Networking: Cache component.

2

How do I fix CVE-2026-2791?

To fix CVE-2026-2791, update your Firefox to version 148 or later, or update Firefox ESR to version 140.8 or later.

3

Which versions of Firefox are affected by CVE-2026-2791?

CVE-2026-2791 affects Firefox versions prior to 148 and Firefox ESR versions prior to 140.8.

4

What components are impacted by CVE-2026-2791?

CVE-2026-2791 impacts the Networking: Cache component within the affected versions of Firefox.

5

Is CVE-2026-2791 a remote exploit flaw?

CVE-2026-2791 could potentially allow an attacker to exploit the mitigation bypass remotely, posing a security risk.

Company

Resources

Contact

SecAlerts Pty Ltd.
132 Wickham Terrace
Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
By using SecAlerts services, you agree to our services end-user license agreement. This website is safeguarded by reCAPTCHA and governed by the Google Privacy Policy and Terms of Service. All names, logos, and brands of products are owned by their respective owners, and any usage of these names, logos, and brands for identification purposes only does not imply endorsement. If you possess any content that requires removal, please get in touch with us.
© 2026 SecAlerts Pty Ltd.
ABN: 70 645 966 203, ACN: 645 966 203