REDHAT-BUG-2503456: High severity Mozilla Firefox ESR vulnerability

Published Jul 21, 2026
·
Updated

Memory safety bugs present in Firefox ESR 115.37, Firefox ESR 140.12 and Firefox 152. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 153, Firefox ESR 115.38, and Firefox ESR 140.13.

Affected Software

1 affected component
Mozilla Firefox ESR=115.37, =140.12, =152

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 153
  2. Upgrade

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

    Fixed in 115.38
  3. Upgrade

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

    Fixed in 140.13

Event History

Jul 21, 2026
Data Sourced
via Red Hat·01:03 PM
DescriptionSeverityAffected Software
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Frequently Asked Questions

1

What is the severity of REDHAT-BUG-2503456?

The severity of REDHAT-BUG-2503456 is rated high at 7.

2

What types of vulnerabilities does REDHAT-BUG-2503456 include?

REDHAT-BUG-2503456 includes memory safety bugs that may lead to memory corruption and potential arbitrary code execution.

3

How do I fix REDHAT-BUG-2503456?

To fix REDHAT-BUG-2503456, upgrade to Firefox version 153 or later, or the updated versions of Firefox ESR.

4

Are these memory safety bugs present in earlier versions of Firefox?

Yes, the memory safety bugs in REDHAT-BUG-2503456 are present in Firefox ESR 115.37, 140.12, and Firefox 152.

5

What is the risk associated with REDHAT-BUG-2503456?

The risk associated with REDHAT-BUG-2503456 is rated at 33, indicating a significant threat to system security.

Contact

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