MongoDB libmongocrypt up to 1.21.0 encoding error

Summaryinfo

A vulnerability, which was classified as critical, has been found in MongoDB libmongocrypt up to 1.21.0. Affected is an unknown function. Performing a manipulation results in encoding error. This vulnerability is identified as CVE-2026-114655. The attack can be initiated remotely. There is not any exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in MongoDB libmongocrypt up to 1.21.0. It has been classified as critical. This affects an unknown functionality. The manipulation with an unknown input leads to a encoding error vulnerability. CWE is classifying the issue as CWE-172. The product does not properly encode or decode the data, resulting in unexpected values. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

libmongocrypt builds requests to external key management services (AWS, Azure and GCP) by inserting values from key vault documents, KMS provider configuration and KMS responses into request lines, headers and signed request bodies without validating or encoding them for each context. A user with write access to the key vault collection can alter the structure of these requests, including adding members to request bodies and token claims that the library then signs with the application's credentials. This may result in key management operations being performed with parameters the application did not intend.

It is possible to read the advisory at jira.mongodb.org. This vulnerability is uniquely identified as CVE-2026-114655 since 10/21/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. The technical details are unknown and an exploit is not publicly available.

Upgrading to version 1.21.1 eliminates this vulnerability.

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Productinfo

Type

• Database Software

Vendor

• MongoDB

Name

• libmongocrypt

Version

• 1.0
• 1.1
• 1.2
• 1.3
• 1.4
• 1.5
• 1.6
• 1.7
• 1.8
• 1.9
• 1.10
• 1.11
• 1.12
• 1.13
• 1.14
• 1.15
• 1.16
• 1.17
• 1.18
• 1.19
• 1.20
• 1.21.0

License

• open-source

CPE 2.3info

• 🔒
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CPE 2.2info

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