Facebook mvfst prior 2025.07.07.00 QUIC Session heap-based overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.3$0-$5k0.00

Summaryinfo

A vulnerability marked as critical has been reported in Facebook mvfst. This vulnerability affects unknown code of the component QUIC Session Handler. The manipulation leads to heap-based overflow. This vulnerability is uniquely identified as CVE-2025-30403. No exploit exists. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Facebook mvfst. It has been rated as critical. This issue affects an unknown code of the component QUIC Session Handler. The manipulation with an unknown input leads to a heap-based overflow vulnerability. Using CWE to declare the problem leads to CWE-122. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). Impacted is confidentiality, integrity, and availability. The summary by CVE is:

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.

It is possible to read the advisory at facebook.com. The identification of this vulnerability is CVE-2025-30403 since 03/21/2025. The exploitation is known to be easy. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 07/11/2025).

Upgrading to version 2025.07.07.00 eliminates this vulnerability. Applying the patch 65b297332191de6e867c4a3139a233fc84c0e7e0 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

Vendor

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.5
VulDB Meta Temp Score: 5.3

VulDB Base Score: 5.5
VulDB Temp Score: 5.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Heap-based overflow
CWE: CWE-122 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: mvfst 2025.07.07.00
Patch: 65b297332191de6e867c4a3139a233fc84c0e7e0

Timelineinfo

03/21/2025 CVE reserved
07/11/2025 +111 days Advisory disclosed
07/11/2025 +0 days VulDB entry created
07/11/2025 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: facebook.com
Status: Confirmed

CVE: CVE-2025-30403 (🔒)
GCVE (CVE): GCVE-0-2025-30403
GCVE (VulDB): GCVE-100-316187

Entryinfo

Created: 07/11/2025 22:37
Changes: 07/11/2025 22:37 (57)
Complete: 🔍
Cache ID: 216::103

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