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.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
None
No data leak
Integrity
None
No data modification
Availability
High
Complete denial of service
CVSS Vector v4.0
Weakness Type (CWE)
Vulnerable Products 1
| Configuration | From (including) | Up to (excluding) |
|---|---|---|
|
Amazon Aws-Smithy-Json
cpe:2.3:a:amazon:aws-smithy-json:*:*:*:*:*:rust:*:*
|
— |
0.62.7
|
References 3
https://aws.amazon.com/security/security-bulletins/2026-067-aws/
ff89ba41-3aa1-4d27-914a-91399e9639e5
https://crates.io/crates/aws-smithy-json/0.62.7
ff89ba41-3aa1-4d27-914a-91399e9639e5
https://github.com/smithy-lang/smithy-rs/security/advisories/GHSA-8ffr-xgwf-xj56
ff89ba41-3aa1-4d27-914a-91399e9639e5