aws-smithy-json: Uncontrolled recursion in the aws-smithy-json unknown-key skip path allows unauthenticated remote denial of service in smithy-rs generated servers
### Summary Smithy-RS is a Rust code generation and runtime framework that generates HTTP clients and servers from Smithy interface definitions, powering the AWS SDK for Rust and custom service implementations. An issue exists which allows uncontrolled recursion in the unknown-key skip path of the Amazon aws-smithy-json runtime crate in versions 0.62.6 and earlier. ### Impact 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. Impacted versions: aws-smithy-json <= 0.62.6 ### Patches This issue has been addressed in aws-smithy-json version 0.62.7. We recommend upgrading to the latest version and ensuring any forked or derivative code is patched to incorporate the new fixes. ### Workarounds There are no workarounds besides updating to the patched version. ### References If you have any questions or comments about this advisory, AWS asks that you contact [AWS/Amazon] Security via their [vulnerability reporting page](https://aws.amazon.com/security/vulnerability-reporting) or directly via email to [aws-security@amazon.com](mailto:aws-security@amazon.com). Please do not create a public GitHub issue.
GHSA-8ffr-xgwf-xj56
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: osv:GHSA-8ffr-xgwf-xj56
aws-smithy-json
Source reference: /affected/0/package/name
- Affected versions
- Not stated in this record
- Fixed versions
- 0.62.7
Source reference:
/affected/0/ranges - Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"ranges": [
{
"type": "SEMVER",
"events": [
{
"introduced": "0"
},
{
"fixed": "0.62.7"
}
]
}
],
"package": {
"name": "aws-smithy-json",
"purl": "pkg:cargo/aws-smithy-json",
"ecosystem": "crates.io"
},
"database_specific": {
"source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-8ffr-xgwf-xj56/GHSA-8ffr-xgwf-xj56.json",
"last_known_affected_version_range": "<= 0.62.6"
}
}
]- Related CVEs
- CVE-2026-18140
Source reference:
/aliases
Publisher severity
high
Source reference: /database_specific/severity
- Event
- #72188 · Revision 1
- Added to Heist Feed
- Publisher date