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

10 Aug 2026, 20:04

Type	Values Removed	Values Added
First Time		Amazon Amazon aws-smithy-json
CPE		cpe:2.3:a:amazon:aws-smithy-json::::::rust::*
References	~~() https://aws.amazon.com/security/security-bulletins/2026-067-aws/ -~~	() https://aws.amazon.com/security/security-bulletins/2026-067-aws/ - Vendor Advisory
References	~~() https://crates.io/crates/aws-smithy-json/0.62.7 -~~	() https://crates.io/crates/aws-smithy-json/0.62.7 - Product
References	~~() https://github.com/smithy-lang/smithy-rs/security/advisories/GHSA-8ffr-xgwf-xj56 -~~	() https://github.com/smithy-lang/smithy-rs/security/advisories/GHSA-8ffr-xgwf-xj56 - Vendor Advisory

30 Jul 2026, 19:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-30 19:17

Updated : 2026-08-10 20:04

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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