CVE-2026-84971

Improper handling of an unexpected value size in the decryption path of a client-side encryption library can cause a failed internal check that terminates the process using the library. A party able to place a suitably formed encrypted value where an application will decrypt it, or able to control the responses the application receives, may cause that application to stop running.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://jira.mongodb.org/browse/MONGOCRYPT-971	Vendor Advisory Issue Tracking Patch

Configurations

Configuration 1 (hide)

cpe:2.3:a:mongodb:libmongocrypt:*:*:*:*:*:*:*:*

History

17 Sep 2026, 13:59

Type	Values Removed	Values Added
First Time		Mongodb Mongodb libmongocrypt
References	~~() https://jira.mongodb.org/browse/MONGOCRYPT-971 -~~	() https://jira.mongodb.org/browse/MONGOCRYPT-971 - Vendor Advisory, Issue Tracking, Patch
CPE		cpe:2.3:a:mongodb:libmongocrypt::::::::

Information

Published : 2026-09-03 15:17

Updated : 2026-09-17 13:59

NVD link : CVE-2026-84971

Mitre link : CVE-2026-84971

CVE.ORG link : CVE-2026-84971

JSON object : View

Products Affected

mongodb

libmongocrypt

CWE

CWE-617

Reachable Assertion

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