CVE-2026-92017: Privilege escalation in the DOM: Service Workers component

Published Sep 15, 2026
·
Updated

Privilege escalation in the DOM: Service Workers component. This vulnerability was fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3.

Affected Software

16 affected componentsFixes available
Mozilla Firefox
Mozilla Firefox ESR
Mozilla Firefox<156
156
Mozilla Firefox ESR<153.3
153.3
Mozilla Firefox ESR<140.16
140.16
Mozilla Firefox ESR<115.41
115.41
Mozilla Thunderbird<156
156
Mozilla Thunderbird<140.16
140.16
Mozilla Thunderbird<153.3
153.3
Mozilla Firefox<115.41.0
Mozilla Firefox>=116.0<140.16.0
Mozilla Firefox>=141.0<153.3.0
Mozilla Firefox>=154.0.0<156.0.0
Mozilla Thunderbird<140.16.0
Mozilla Thunderbird>=141.0<153.3.0
Mozilla Thunderbird>=154.0<156.0

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 156
  2. Upgrade

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

    Fixed in 153.3
  3. Upgrade

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

    Fixed in 140.16
  4. Upgrade

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

    Fixed in 115.41
  5. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 156
  6. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 115.41
  7. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 140.16
  8. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 153.3
  9. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 156
  10. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 140.16
  11. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 153.3

Event History

Sep 15, 2026
CVE Published
via Mozilla·12:00 AM
Data Sourced
via Mozilla·12:00 AM
DescriptionSeverityAffected Software
Updated
via Mozilla·12:00 AM
Affected Software
CVE Published
via MITRE·12:33 PM
Data Sourced
via MITRE·12:33 PM
Description
Data Sourced
via NVD·01:16 PM
DescriptionSeverityWeaknessAffected Software
Sep 16, 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.

Frequently Asked Questions

1

Which Firefox releases contain the fix?

The fix is included in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, and Firefox ESR 153.3.

2

How can I determine whether my deployment has received the fix?

Check the installed Firefox or Firefox ESR version against the listed fixed release for its release branch. Deploy the applicable fixed version if the installation is not yet at that version.

Company

Resources

Contact

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