CVE-2026-18140

Uncontrolled recursion in the unknown-key skip path of the aws-smithy-json runtime crate before 0.62.7, which the smithy-rs code generator invokes from every generated struct deserializer, might allow remote unauthenticated users to cause a denial of service (process abort via stack exhaustion) via a single small HTTP request containing deeply nested JSON to a smithy-rs generated server. To remediate this issue, users should upgrade to aws-smithy-json 0.62.7 or later and rebuild.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://aws.amazon.com/security/security-bulletins/2026-067-aws/	Vendor Advisory
https://crates.io/crates/aws-smithy-json/0.62.7	Product
https://github.com/smithy-lang/smithy-rs/security/advisories/GHSA-8ffr-xgwf-xj56	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:amazon:aws-smithy-json:*:*:*:*:*:rust:*:*

History

23 Oct 2026, 22:10

Type	Values Removed	Values Added
Summary		(es) Recursión incontrolada en la ruta de omisión de clave desconocida del crate de tiempo de ejecución aws-smithy-json anterior a 0.62.7, que el generador de código smithy-rs invoca desde cada deserializador de estructura generado, podría permitir a usuarios remotos no autenticados causar una denegación de servicio (aborto de proceso por agotamiento de pila) a través de una única pequeña solicitud HTTP que contiene JSON profundamente anidado a un servidor generado por smithy-rs. Para remediar este problema, los usuarios deberían actualizar a aws-smithy-json 0.62.7 o posterior y reconstruir.

Information

Published : 2026-07-30 19:17

Updated : 2026-10-23 22:10

NVD link : CVE-2026-18140

Mitre link : CVE-2026-18140

CVE.ORG link : CVE-2026-18140

JSON object : View

Products Affected

amazon

aws-smithy-json

CWE

CWE-674

Uncontrolled Recursion

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