RewindexCVEsAmazon Web Services
CVE-2026-15957: Uncontrolled recursion in smithy-rs generated JSON, CBOR, and XML deserializers allows unauthenticated remote denial of service via recursive shapes
Description
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. Uncontrolled recursion in the JSON, CBOR, and XML deserializer functions emitted by Amazon smithy-rs code generation could allow remote attackers to cause a denial of service (process abort via stack exhaustion) via a small request containing deeply nested data for a recursive model shape to a generated SDK or server. To mitigate this issue, users should upgrade to aws-sdk-rust release-2026-06-02 or later. Users building custom servers with smithy-rs codegen should regenerate from smithy-rs release-2026-06-01 or later.
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H · CWE-674
Tracked companies
Mapped from the CVE’s affected-product data, NVD CPE matches, vendor advisories or package feeds. A mapping means the vendor’s software is named, not that its hosted service was exposed.
Status incidents that name it
No tracked status incident names this CVE.
Affected vendors and products
AWS: aws-sdk-rust
References
- CVE record on cve.org (opens in new tab)
- NVD entry (opens in new tab)
- aws.amazon.com/security/security-bulletins/2026-061-aws/ (opens in new tab)
- github.com/awslabs/aws-sdk-rust/releases/tag/release-2026-06-02 (opens in new tab)
- github.com/smithy-lang/smithy-rs/security/advisories/GHSA-4f2p-7j38-4xrg (opens in new tab)
- CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (opens in new tab)
- This product uses data from the NVD API but is not endorsed or certified by the NVD. (opens in new tab)
- Known Exploited Vulnerabilities catalog from CISA. (opens in new tab)
- EPSS scores from FIRST (Exploit Prediction Scoring System). (opens in new tab)