CVE-2026-106429
Medium
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.
SeverityMedium
CVSS6.5
Exploit probability—
Product
Mongodb Libmongocrypt
PublishedOct 8, 2026
First seenOct 8, 2026
Weakness typeCWE-191CWE-191
How to fix
Update
- MongoDB libmongocrypt1.20.5 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| MongoDB libmongocrypt | 1.1.0 ≤ v < 1.20.5 | 1.20.5 |
Check your version
Choose the product and enter the version you run to see whether it falls in the affected range.
In the Intelligence 360 plan
Attack Surface Management
See the assets tied to your domains, the technologies they run and known vulnerabilities in one list.