CVE-2026-12318: Incorrect boundary conditions in the Libraries component in NSS

Published Jun 16, 2026
·
Updated

Incorrect boundary conditions in the Libraries component in NSS. This vulnerability was fixed in Firefox 152 and Thunderbird 152.

Affected Software

6 affected componentsFixes available
Mozilla Thunderbird<152
152
Mozilla Firefox<152.0.0
Mozilla Thunderbird<152.0.0
Mozilla Firefox<152
152
debian/firefox<=152.0.4-1
debian/nss<=2:3.61-1+deb11u3, <=2:3.61-1+deb11u5, <=2:3.87.1-1+deb12u2, <=2:3.110-1+deb13u1, <=2:3.110-1+deb13u2
2:3.124-1

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 152
  2. Upgrade

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

    Fixed in 2:3.124-1
  3. Upgrade

    Upgrade Firefox / Thunderbird (NSS Libraries component) to a version that resolves this vulnerability.

    Fixed in 152

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·11:52 AM
Data Sourced
via MITRE·11:52 AM
Description
Data Sourced
via NVD·01:16 PM
DescriptionSeverityWeaknessAffected Software
Jun 29, 2026
Data Sourced
via Launchpad·09:00 PM
Description
Jul 1, 2026
Data Sourced
via Ubuntu·09:00 PM
RemedyDescriptionSeverityAffected Software
Data Sourced
via Debian·09:01 PM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2026-12318?

CVE-2026-12318 has a high severity rating of 7.3 according to the CVSS 3.1 metrics.

2

How do I fix CVE-2026-12318?

To fix CVE-2026-12318, update to Firefox version 152 or Thunderbird version 152.

3

What type of vulnerability is CVE-2026-12318?

CVE-2026-12318 is classified as a buffer overflow vulnerability due to incorrect boundary conditions.

4

Which software is affected by CVE-2026-12318?

CVE-2026-12318 affects Mozilla Firefox and Mozilla Thunderbird.

5

When was CVE-2026-12318 published?

CVE-2026-12318 was published on June 16, 2026.

Contact

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