Denial-of-Service Vulnerability in NSS Component of Firefox
CVE-2026-4727

7.5HIGH

Key Information:

Vendor

Mozilla
Status
Firefox
Thunderbird
Vendor
CVE Published:
24 March 2026

What is CVE-2026-4727?

A vulnerability identified in the Libraries component of NSS may allow an attacker to trigger a denial-of-service condition in Firefox versions earlier than 149. This can disrupt normal operation, potentially leading to application crashes and affecting user experience. Users are encouraged to update to the latest version to mitigate the risk associated with this vulnerability.

Affected Version(s)

Firefox < 149

Thunderbird < 149

References

https://bugzilla.mozilla.org/show_bug.cgi?id=2008112
https://www.mozilla.org/security/advisories/mfsa2026-20/
https://www.mozilla.org/security/advisories/mfsa2026-23/

CVSS V3.1

Score:
7.5
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Cody
.