CVE-2026-6766
Received Received - Intake
Boundary Error in NSS Libraries Causes Potential Security Risk

Publication date: 2026-04-21

Last updated on: 2026-04-22

Assigner: Mozilla Corporation

Description
Incorrect boundary conditions in the Libraries component in NSS. This vulnerability was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.
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Meta Information
Published
2026-04-21
Last Modified
2026-04-22
Generated
2026-06-16
AI Q&A
2026-04-21
EPSS Evaluated
2026-06-15
NVD
CVE-2026-6766
EUVD
EUVD-2026-24107
Affected Vendors & Products
Showing 3 associated CPEs
Vendor Product Version / Range
mozilla firefox to 150.0 (exc)
mozilla firefox to 140.10.0 (exc)
mozilla thunderbird to 140.10.0 (exc)
Helpful Resources
Exploitability
CWE
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KEV
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CWE ID Description
CWE-754 The product does not check or incorrectly checks for unusual or exceptional conditions that are not expected to occur frequently during day to day operation of the product.
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Executive Summary

This vulnerability involves incorrect boundary conditions in the Libraries component of NSS (Network Security Services). It means that certain checks or limits within the code were not properly enforced, potentially leading to unexpected behavior or security issues.

The issue was addressed and fixed in Firefox version 150 and Firefox ESR 140.10.

Mitigation Strategies

The vulnerability was fixed in Firefox 150 and Firefox ESR 140.10. To mitigate this vulnerability, you should update your Firefox or Firefox ESR browsers to at least these versions.

Impact Analysis

This vulnerability involves incorrect boundary conditions in the Libraries component of NSS, which could potentially lead to security issues in affected versions of Mozilla Firefox and Firefox ESR before the fixes were applied.

It was fixed in Firefox 150 and Firefox ESR 140.10, so using versions prior to these may expose you to risks related to this vulnerability.

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