CVE-2026-84138: Denial-of-service in the PDF Viewer component

Published Sep 1, 2026
·
Updated

Denial-of-service in the PDF Viewer component. This vulnerability was fixed in Firefox 155.

Affected Software

2 affected componentsFixes available
Mozilla Firefox<155
155
Mozilla Firefox PDF Viewer<155

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 155
  2. Upgrade

    Upgrade Firefox PDF Viewer to a version that resolves this vulnerability.

    Fixed in 155

Event History

Sep 1, 2026
CVE Published
via Mozilla·12:00 AM
Data Sourced
via Mozilla·12:00 AM
DescriptionSeverityAffected Software
CVE Published
via MITRE·12:19 PM
Data Sourced
via MITRE·12:19 PM
Description

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

Which Firefox versions are affected?

The issue was fixed in Firefox 155. The provided information does not specify the earliest affected version.

2

What is the impact of successful exploitation?

Successful exploitation can cause a denial of service in the PDF Viewer component. The provided information does not describe impacts beyond service disruption.

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