REDHAT-BUG-2503439: High severity Mozilla Firefox vulnerability

Published Jul 21, 2026
·
Updated

JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 153, Firefox ESR 115.38, and Firefox ESR 140.13.

Affected Software

1 affected component
Mozilla Firefox=153, =115.38, =140.13

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 153
  2. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 115.38
  3. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 140.13

Event History

Jul 21, 2026
Data Sourced
via Red Hat·01:02 PM
DescriptionSeverityAffected Software
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Frequently Asked Questions

1

What is the severity of REDHAT-BUG-2503439?

The severity of REDHAT-BUG-2503439 is classified as high, with a score of 7.

2

How do I fix REDHAT-BUG-2503439?

REDHAT-BUG-2503439 can be fixed by updating to Firefox version 153 or higher, Firefox ESR 115.38 or higher, or Firefox ESR 140.13 or higher.

3

What does REDHAT-BUG-2503439 affect?

REDHAT-BUG-2503439 affects the JavaScript Engine due to JIT miscompilation issues in Mozilla Firefox.

4

When was REDHAT-BUG-2503439 published?

REDHAT-BUG-2503439 was published on July 21, 2026.

5

Where can I find more information about REDHAT-BUG-2503439?

For more information about REDHAT-BUG-2503439, you can refer to the related Red Hat advisories.

Contact

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