CVE-2025-8029: javascript: URLs executed on object and embed tags

Published Jul 22, 2025
·
Updated

Firefox executed javascript: URLs when used in object and embed tags.

Other sources

Thunderbird executed javascript: URLs when used in object and embed tags. This vulnerability affects Firefox < 141, Firefox ESR < 128.13, Firefox ESR < 140.1, Thunderbird < 141, Thunderbird < 128.13, and Thunderbird < 140.1.

Red Hat

Thunderbird executed javascript: URLs when used in object and embed tags. This vulnerability was fixed in Firefox 141, Firefox ESR 128.13, Firefox ESR 140.1, Thunderbird 141, Thunderbird 128.13, and Thunderbird 140.1.

MITRE

Thunderbird executed javascript: URLs when used in object and embed tags.

Mozilla

Affected Software

12 affected componentsFixes available
Mozilla Firefox<141
141
Mozilla Firefox ESR<128.13
128.13
Mozilla Firefox ESR<140.1
140.1
Mozilla Thunderbird<128.13
128.13
Mozilla Thunderbird<141
141
Mozilla Thunderbird<140.1
140.1
Mozilla Firefox<128.13.0
Mozilla Firefox<141.0
Mozilla Firefox>=140.0<140.1.0
Mozilla Thunderbird<128.13.0
Mozilla Thunderbird<141.0
Mozilla Thunderbird>=140.0<140.1.0

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 128.13
  2. Upgrade

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

    Fixed in 140.1
  3. Upgrade

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

    Fixed in 141
  4. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 141
  5. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 128.13
  6. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 140.1
  7. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 141
  8. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 128.13
  9. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 140.1

Event History

Jul 22, 2025
CVE Published
via Mozilla·12:00 AM
Data Sourced
via Mozilla·12:00 AM
DescriptionSeverityAffected Software
Updated
via Mozilla·12:00 AM
Affected Software
Updated
via Mozilla·12:00 AM
DescriptionAffected Software
CVE Published
via MITRE·08:49 PM
Data Sourced
via MITRE·08:49 PM
Description
Data Sourced
via Red Hat·09:02 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·09:15 PM
DescriptionSeverityWeaknessAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is the severity of CVE-2025-8029?

CVE-2025-8029 has been designated a high severity vulnerability due to the potential execution of malicious JavaScript.

2

How do I fix CVE-2025-8029?

To fix CVE-2025-8029, update to Mozilla Firefox version 141 or Firefox ESR version 128.13 or 140.1.

3

What versions of Firefox are affected by CVE-2025-8029?

CVE-2025-8029 affects Mozilla Firefox versions up to 141 and Firefox ESR versions up to 128.13 and 140.1.

4

What type of vulnerability is CVE-2025-8029?

CVE-2025-8029 is a JavaScript execution vulnerability caused by improper handling of javascript: URLs in object and embed tags.

5

Who should be concerned about CVE-2025-8029?

Users of affected versions of Mozilla Firefox and Firefox ESR should be concerned about CVE-2025-8029 and should upgrade their browsers.

Contact

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