8.1

CVE-2025-30403: facebook mvfst

CVSS: 8.1v3.1HighDeferred
Published 11-07-2025Last modified 11-07-2025
Open JSON

Vulnerability summary

CVE-2025-30403 is a high (CVSS 8.1) vulnerability in facebook mvfst. EPSS estimates a 0.33% chance of exploitation in the next 30 days, higher than 24.6% of scored vulnerabilities.

Overall risk
32/100
0100
Medium · default modelHow is this calculated?
CVSS score
8.1/10
010
High · v3.1 (CVE.org)
EPSS score
0.33%
0%100%
Low · +0.04 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 11-07-2025
    PublishedVulnerability first disclosed.
  2. 11-07-2025
    Last modifiedVulnerability information updated.

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.

CVSS metrics

2 scores · 2 sources · 1 version

EPSS trend

Probability

0.33%

Chance of exploitation in the next 30 days

Percentile

25%

Versus all other CVEs

30-day change

+0.04 pp

From 0.29% on 20-09-2026

20-09-202620-10-2026
EPSS score
0.33%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

No weakness data has been published for this record.

Affected systems

Facebook1 product
  • mvfst≥ v2025.03.24.00, < v2025.07.07.00

1 vendor · 1 product

References

2 links