CVE-2026-106429

Application denial of service via malformed KMS endpoint in MongoDB libmongocrypt

MEDIUM
6.5
CVSS Score
Published: October 8, 2026 at 06:54 PM UTC
Updated: October 8, 2026 at 08:49 PM UTC
1 product affected across 1 vendorLibmongocrypt

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Severity
MEDIUM6.5
Exploit prediction
EPSS 0.3%
SSVC
No known exploit

Description

An integer underflow in the KMS endpoint-parsing logic of MongoDB libmongocrypt can cause an allocation failure that terminates the application process. This can occur when an authenticated user modifies a key document in the key vault collection, or when an application accepts a KMS endpoint containing a colon after its path or query during key creation. The issue does not access memory outside its allocated bounds.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

1.1.0 ≤ v < 1.20.51.1.0

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

References (1)

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

6.5MEDIUMmongodb
Attack Vector
NETWORK
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusUNDERGOING ANALYSIS
CWE
CWE-191

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