CVE-2026-15957

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.

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/2026-061-aws/
https://github.com/awslabs/aws-sdk-rust/releases/tag/release-2026-06-02
https://github.com/smithy-lang/smithy-rs/security/advisories/GHSA-4f2p-7j38-4xrg

Configurations

No configuration.

History

No history.

Information

Published : 2026-07-21 20:16

Updated : 2026-07-22 20:37

NVD link : CVE-2026-15957

Mitre link : CVE-2026-15957

CVE.ORG link : CVE-2026-15957

JSON object : View

Products Affected

No product.

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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