REDHAT-BUG-2503423: Medium severity Mozilla Firefox vulnerability

Published Jul 21, 2026
·
Updated

Site isolation issue in the Networking: HTTP component. This vulnerability was fixed in Firefox 153 and Firefox ESR 140.13.

Affected Software

1 affected component
Mozilla Firefox<153, <140.13

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Firefox (Networking: HTTP) to a version that resolves this vulnerability.

    Fixed in 153
  2. Upgrade

    Upgrade Firefox ESR (Networking: HTTP) to a version that resolves this vulnerability.

    Fixed in 140.13

Event History

Jul 21, 2026
Data Sourced
via Red Hat·01:01 PM
DescriptionSeverityAffected Software
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Frequently Asked Questions

1

What is the severity of REDHAT-BUG-2503423?

The severity of REDHAT-BUG-2503423 is categorized as medium with a score of 4.

2

How do I fix REDHAT-BUG-2503423?

To fix REDHAT-BUG-2503423, upgrade to Firefox version 153 or Firefox ESR version 140.13.

3

What component is affected by REDHAT-BUG-2503423?

REDHAT-BUG-2503423 affects the Networking: HTTP component.

4

When was REDHAT-BUG-2503423 published?

REDHAT-BUG-2503423 was published on July 21, 2026.

5

What issue does REDHAT-BUG-2503423 address?

REDHAT-BUG-2503423 addresses a site isolation issue in Mozilla Firefox.

Contact

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