CVE-2026-4727
Denial-of-service in the Libraries component in NSS
HIGH
7.5
CVSS Score
Published: March 24, 2026 at 12:30 PM UTC
Updated: June 17, 2026 at 10:57 AM UTC
2 products affected across 1 vendorFirefoxThunderbird
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Severity
HIGH7.5
Exploit prediction
EPSS 0.6%
SSVC
No known exploit
Description
Denial-of-service in the Libraries component in NSS. This vulnerability affects Firefox < 149.
Affected
Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.
Remediation
No guide yetNo remediation guidance has been written for this CVE yet. What the record does show:
Patch and advisory references
References (3)
SSVC — Action Prioritization
SSVCNo known exploitAutomatablePartial impact
SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.
CVSS
7.5HIGHCISA-ADP
- Attack Vector
- NETWORK
- Complexity
- LOW
- Privileges
- NONE
- User Interaction
- NONE
- Scope
- UNCHANGED
- Confidentiality
- NONE
- Integrity
- NONE
- Availability
- HIGH
Vector?
Quick Info
StatusMODIFIED
CWE
CWE-400
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