CVE-2026-4718
Undefined behavior in the WebRTC: Signaling component
HIGH
8.1
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
HIGH8.1
Exploit prediction
EPSS 0.5%
SSVC
No known exploit
Description
Undefined behavior in the WebRTC: Signaling component. This vulnerability affects Firefox < 149 and Firefox ESR < 140.9.
Affected
Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.
v < 140.9.0v < 149.0
Vendor states this is fixed in 140.9 (unaffected)
Vendor states this is fixed in 149 (unaffected)
v < 140.9.0v < 149.0
Vendor states this is fixed in 140.9 (unaffected)
Vendor states this is fixed in 149 (unaffected)
Remediation
No guide yetNo remediation guidance has been written for this CVE yet. What the record does show:
References (5)
SSVC — Action Prioritization
SSVCNo known exploitNot automatableTotal impact
SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.
CVSS
8.1HIGHCISA-ADP
- Attack Vector
- NETWORK
- Complexity
- LOW
- Privileges
- NONE
- User Interaction
- REQUIRED
- Scope
- UNCHANGED
- Confidentiality
- HIGH
- Integrity
- HIGH
- Availability
- NONE
Vector?
Quick Info
StatusMODIFIED
CWE
CWE-758
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