CVE-2025-9181: Uninitialized memory in the JavaScript Engine component

Published Aug 19, 2025
·
Updated

Uninitialized memory in the JavaScript Engine component.

Affected Software

28 affected componentsFixes available
Mozilla Firefox<142
Mozilla Firefox ESR<128.14, <140.2
Mozilla Thunderbird<142
Mozilla Thunderbird<142
142
Mozilla Thunderbird<140.2
140.2
Mozilla Firefox ESR<140.2
140.2
Mozilla Firefox<128.14.0
Mozilla Firefox<142.0
Mozilla Firefox>=140.0<140.2.0
Mozilla Thunderbird<128.14.0
Mozilla Thunderbird<142.0
Mozilla Thunderbird>=140.0<140.2.0
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<142
142
Mozilla Firefox ESR<128.14
128.14
Mozilla Thunderbird<128.14
128.14
debian/firefox
159.0-1
debian/firefox-esr
140.12.0esr-1~deb12u1153.6.0esr-1~deb12u2140.15.0esr-1~deb13u1153.6.0esr-1~deb13u1153.5.1esr-1153.6.0esr-1
debian/thunderbird
1:140.12.0esr-1~deb12u11:153.6.0esr-1~deb12u11:140.12.0esr-1~deb13u11:153.6.0esr-1~deb13u11:153.5.0esr-11:153.6.0esr-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 142
  2. Upgrade

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

    Fixed in 140.2
  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 128.14
  5. Upgrade

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

    Fixed in 159.0-1
  6. Upgrade

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

    Fixed in 140.12.0esr-1~deb12u1Fixed in 153.6.0esr-1~deb12u2Fixed in 140.15.0esr-1~deb13u1Fixed in 153.6.0esr-1~deb13u1Fixed in 153.5.1esr-1Fixed in 153.6.0esr-1
  7. Upgrade

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

    Fixed in 1:140.12.0esr-1~deb12u1Fixed in 1:153.6.0esr-1~deb12u1Fixed in 1:140.12.0esr-1~deb13u1Fixed in 1:153.6.0esr-1~deb13u1Fixed in 1:153.5.0esr-1Fixed in 1:153.6.0esr-1
  8. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 142
  9. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 128.14
  10. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 140.2
  11. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 142
  12. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 128.14
  13. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 140.2

Event History

Aug 19, 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·08:33 PM
Data Sourced
via MITRE·08:33 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-2025-9181?

CVE-2025-9181 is considered a high-severity vulnerability due to the potential for memory corruption.

2

How do I fix CVE-2025-9181?

To fix CVE-2025-9181, users should upgrade to the latest versions of Firefox or Thunderbird that are not affected by this vulnerability.

3

Which versions are affected by CVE-2025-9181?

CVE-2025-9181 affects Firefox versions prior to 142, Firefox ESR versions prior to 128.14 and 140.2, and Thunderbird versions prior to 142.

4

What are the potential impacts of CVE-2025-9181?

The potential impacts of CVE-2025-9181 include unauthorized access to sensitive information and the possibility of remote code execution.

5

Is CVE-2025-9181 specific to any operating systems?

CVE-2025-9181 is not specific to any operating systems but affects the mentioned versions of Mozilla software across various platforms.

Company

Resources

Contact

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