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 was fixed in Firefox 141, Firefox ESR 128.13, Firefox ESR 140.1, Thunderbird 141, Thunderbird 128.13, and Thunderbird 140.1.

— Ubuntu

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.

— Mozilla

Affected Software

25 affected componentsFixes available
Mozilla Firefox ESR<140.1
140.1
Mozilla Thunderbird<140.1
140.1
Mozilla Thunderbird<141
141
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
ubuntu/mozjs52*
ubuntu/mozjs38*
ubuntu/mozjs68*
ubuntu/mozjs52*
ubuntu/mozjs102*
ubuntu/mozjs78*
ubuntu/mozjs91*
ubuntu/thunderbird<1:140.7.1+build1-0ubuntu0.22.04.1
1:140.7.1+build1-0ubuntu0.22.04.1
ubuntu/mozjs102*
ubuntu/mozjs115*
Mozilla Firefox<141
141
Mozilla Firefox ESR<128.13
128.13
Mozilla Thunderbird<128.13
128.13
debian/firefox
160.0-1
debian/firefox-esr
140.12.0esr-1~deb12u1153.7.0esr-1~deb12u1140.15.0esr-1~deb13u1153.7.0esr-1~deb13u1153.5.1esr-1153.7.0esr-1
debian/thunderbird
1:140.12.0esr-1~deb12u11:153.7.0esr-1~deb12u11:140.12.0esr-1~deb13u11:153.7.0esr-1~deb13u11:153.5.0esr-11:153.7.0esr-1

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 140.1
  2. Upgrade

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

    Fixed in 141
  3. Upgrade

    Upgrade ubuntu/thunderbird to a version that resolves this vulnerability.

    Fixed in 1:140.7.1+build1-0ubuntu0.22.04.1
  4. Upgrade

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

    Fixed in 128.13
  5. Upgrade

    Upgrade debian/firefox to a version that resolves this vulnerability.

    Fixed in 160.0-1
  6. Upgrade

    Upgrade debian/firefox-esr to a version that resolves this vulnerability.

    Fixed in 140.12.0esr-1~deb12u1Fixed in 153.7.0esr-1~deb12u1Fixed in 140.15.0esr-1~deb13u1Fixed in 153.7.0esr-1~deb13u1Fixed in 153.5.1esr-1Fixed in 153.7.0esr-1
  7. Upgrade

    Upgrade debian/thunderbird to a version that resolves this vulnerability.

    Fixed in 1:140.12.0esr-1~deb12u1Fixed in 1:153.7.0esr-1~deb12u1Fixed in 1:140.12.0esr-1~deb13u1Fixed in 1:153.7.0esr-1~deb13u1Fixed in 1:153.5.0esr-1Fixed in 1:153.7.0esr-1
  8. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 141
  9. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 128.13
  10. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 140.1
  11. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 141
  12. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 128.13
  13. 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
Data Sourced
via Ubuntu·12:00 AM
RemedyDescriptionSeverityAffected 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 OSV·09:15 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·09:15 PM
DescriptionSeverityWeaknessAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

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.

Company

Resources

Contact

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