CVE-2025-30403
HIGH
8.1
CVSS Score
Published: July 11, 2025 at 06:26 PM UTC
Updated: June 17, 2026 at 09:08 AM UTC
1 product affected across 1 vendorMvfst
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Severity
HIGH8.1
Exploit prediction
EPSS 0.3%
SSVC
No known exploit
Description
A heap-buffer-overflow vulnerability is possible in mvfst via a specially crafted message during a QUIC session. This issue affects mvfst versions prior to v2025.07.07.00.
Affected
Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.
v2025.03.24.00 ≤ v < v2025.07.07.002025.03.24.00
Affected range stops below v2025.07.07.00, so it looks safe — our inference, not a vendor statement
Remediation
No guide yetNo remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.
References (2)
x_refsource_CONFIRM
Source: [email protected]
https://github.com/facebook/mvfst/commit/65b297332191de6e867c4a3139a233fc84c0e7e0x_refsource_CONFIRM
Source: [email protected]
https://www.facebook.com/security/advisories/cve-2025-30403SSVC — Action Prioritization
SSVCNo known exploitNot automatablePartial 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
- NONE
- Availability
- HIGH
Vector?
Quick Info
StatusDEFERRED
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