CVE-2026-2781: Integer overflow in the Libraries component in NSS

Published Feb 24, 2026
·
Updated

Integer overflow in the Libraries component in NSS. This vulnerability affects Firefox < 148 and Firefox ESR < 140.8.

Other sources

Integer overflow in the Libraries component in NSS. This vulnerability was fixed in Firefox 148, Firefox ESR 140.8, Thunderbird 148, Thunderbird 140.8, and Firefox ESR 115.35.

— MITRE

Affected Software

9 affected componentsFixes available
Mozilla Firefox<148
148
Mozilla Firefox ESR<140.8
140.8
Mozilla Thunderbird<148
148
Mozilla Thunderbird<140.8
140.8
Mozilla Firefox<140.8.0
Mozilla Firefox<148.0
Mozilla Thunderbird<140.8.0
Mozilla Thunderbird<148.0
Mozilla Firefox ESR<115.35
115.35

Event History

Feb 24, 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·01:33 PM
Data Sourced
via MITRE·01:33 PM
Description
Data Sourced
via Red Hat·02:02 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·02:16 PM
DescriptionSeverityWeaknessAffected Software
Apr 21, 2026
Updated
via Mozilla·12:00 AM
Affected 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-2026-2781?

CVE-2026-2781 has a critical severity rating of 9.8.

2

How do I fix CVE-2026-2781?

To fix CVE-2026-2781, update to Firefox version 148, Firefox ESR version 140.8, Thunderbird version 148, or Thunderbird version 140.8.

3

Which software is affected by CVE-2026-2781?

CVE-2026-2781 affects Mozilla Firefox versions prior to 148, Firefox ESR versions prior to 140.8, and Mozilla Thunderbird versions prior to 148.

4

What type of vulnerability is CVE-2026-2781?

CVE-2026-2781 is classified as an integer overflow vulnerability.

5

When was CVE-2026-2781 published?

CVE-2026-2781 was published on February 24, 2026.

Company

Resources

Contact

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