CVE-2025-10529: Same-origin policy bypass in the Layout component

Published Sep 16, 2025
·
Updated

Same-origin policy bypass in the Layout component. This vulnerability affects Firefox < 143, Firefox ESR < 140.3, Thunderbird < 143, and Thunderbird < 140.3.

Other sources

Same-origin policy bypass in the Layout component. This vulnerability was fixed in Firefox 143, Firefox ESR 140.3, Thunderbird 143, and Thunderbird 140.3.

— Ubuntu

This vulnerability affects Firefox < 143 and Firefox ESR < 140.3.

— Red Hat

Affected Software

22 affected componentsFixes available
Mozilla Firefox<143
Mozilla Firefox ESR<140.3
Mozilla Thunderbird<143
143
Mozilla Firefox<140.3.0
Mozilla Firefox<143.0
Mozilla Thunderbird<143.0
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<143
143
Mozilla Firefox ESR<140.3
140.3
Mozilla Thunderbird<140.3
140.3
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 143
  2. Upgrade

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

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

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

    Fixed in 140.3
  4. Upgrade

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

    Fixed in 160.0-1
  5. 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
  6. 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
  7. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 143
  8. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 140.3
  9. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 143
  10. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 140.3

Event History

Sep 16, 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·12:26 PM
Data Sourced
via MITRE·12:26 PM
Description
Data Sourced
via Red Hat·01:02 PM
DescriptionSeverityAffected Software
Data Sourced
via OSV·01:15 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·01:15 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-2025-10529?

CVE-2025-10529 has been classified as a critical vulnerability affecting certain versions of Firefox.

2

How do I fix CVE-2025-10529?

To remediate CVE-2025-10529, update Firefox to version 143 or Firefox ESR to version 140.3 or later.

3

What versions of Firefox are affected by CVE-2025-10529?

CVE-2025-10529 affects Firefox versions prior to 143 and Firefox ESR versions prior to 140.3.

4

What impact does CVE-2025-10529 have on users?

CVE-2025-10529 could potentially allow remote code execution, putting users at significant risk.

5

Is there a workaround for CVE-2025-10529?

Currently, the best mitigation for CVE-2025-10529 is to immediately update to the latest version of Firefox or Firefox ESR.

Company

Resources

Contact

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