High severity · published Jul 11, 2025
CVE-2025-30403
A heap-buffer-overflow vulnerability is possible in mvfst via a specially crafted message during a QUIC session
8.1
CVSS
0.3%
EPSS
No
On KEV
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 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 26% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MV
mvfst · Facebook
v2025.03.24.00 before v2025.07.07.00 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-30403
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-30403
github.com
https://github.com/facebook/mvfst/commit/65b297332191de6e867c4a3139a233fc84c0e7e0
www.facebook.com
https://www.facebook.com/security/advisories/cve-2025-30403
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CVE-2021-24029
A packet of death scenario is possible in mvfst via a specially crafted message during a QUIC session, which causes a crash via a failed assertion