CVE-2026-12330: Incorrect boundary conditions in the Internationalization component

Published Jun 16, 2026
·
Updated

Incorrect boundary conditions in the Internationalization component. This vulnerability was fixed in Firefox ESR 140.12, Firefox ESR 115.37, and Thunderbird 140.12.

Affected Software

6 affected componentsFixes available
Mozilla Firefox ESR<140.12
140.12
Mozilla Firefox ESR<115.37
115.37
Mozilla Thunderbird<140.12
140.12
Mozilla Firefox<115.37.0
Mozilla Firefox>=140.0<140.12.0
Mozilla Thunderbird>=140.0<140.12.0

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 140.12
  2. Upgrade

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

    Fixed in 115.37
  3. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 140.12
  4. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 115.37
  5. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 140.12

Event History

Jun 16, 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·11:53 AM
Data Sourced
via MITRE·11:53 AM
Description
Data Sourced
via NVD·01:16 PM
DescriptionSeverityWeaknessAffected Software
Data Sourced
via Red Hat·02:01 PM
DescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

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Frequently Asked Questions

1

What is the severity of CVE-2026-12330?

CVE-2026-12330 has a medium severity rating of 5.4 according to the CVSS 3.1 score.

2

How do I fix CVE-2026-12330?

To fix CVE-2026-12330, update to Firefox ESR 140.12, Firefox ESR 115.37, or Thunderbird 140.12.

3

What types of software does CVE-2026-12330 affect?

CVE-2026-12330 affects Mozilla Firefox ESR and Mozilla Thunderbird.

4

What is the risk of exploiting CVE-2026-12330?

The risk associated with CVE-2026-12330 is rated as moderate with a risk score of 34.

5

What is the nature of the issue in CVE-2026-12330?

CVE-2026-12330 involves incorrect boundary conditions in the Internationalization component, leading to potential buffer overflow.

Company

Resources

Contact

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