CVE-2026-15719: Site isolation issue in the DOM: Navigation component

Published Jul 14, 2026
·
Updated

We are aware that exploit code for this is public however we are not aware of any attacks in the wild abusing this flaw.

Affected Software

5 affected componentsFixes available
Mozilla Firefox<152.0.6
152.0.6
Mozilla Firefox ESR<115.38
115.38
Mozilla Firefox ESR<140.13
140.13
Mozilla Firefox<152.0.6
Mozilla Thunderbird<140.13
140.13

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 152.0.6
  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
  4. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 152.0.6
  5. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 115.38
  6. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 140.13
  7. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 140.13

Event History

Jul 14, 2026
CVE Published
via Mozilla·12:00 AM
Data Sourced
via Mozilla·12:00 AM
DescriptionSeverityAffected Software
CVE Published
via MITRE·12:15 PM
Data Sourced
via MITRE·12:15 PM
Description
Data Sourced
via NVD·01:18 PM
DescriptionSeverityAffected Software
Jul 21, 2026
Updated
via Mozilla·12:00 AM
Affected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

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Frequently Asked Questions

1

What is the severity of CVE-2026-15719?

The severity of CVE-2026-15719 is rated as critical with a score of 9.

2

How do I fix CVE-2026-15719?

To fix CVE-2026-15719, update your Mozilla Firefox to version 152.0.6 or later.

3

Is there any known exploitation of CVE-2026-15719 in the wild?

As of now, there are no known attacks in the wild exploiting CVE-2026-15719.

4

What component of Mozilla Firefox is affected by CVE-2026-15719?

CVE-2026-15719 affects the navigation component associated with site isolation in the DOM.

5

What is the publication date of CVE-2026-15719?

CVE-2026-15719 was published on July 14, 2026.

Company

Resources

Contact

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