Live › vulnerability › CVE-2026-119148
The AWS Nitro Enclaves SDK for C has two issues: a use-after-free in the kmstool-enclave example's SetClient handler that lets a process on the parent EC2 instance run code inside the enclave, and a KMS server name built from a caller-supplied region that lets a third party impersonate KMS and inject forged responses such as attacker-chosen key material. Both are fixed in v0.4.6.
Summary written from the sources below. Check the originals before acting.
First seen by InfraStack 2026-10-30 16:50 UTC, 1h before NVD. All times on this page are UTC.
Teams that build applications running inside AWS Nitro Enclaves using the aws-nitro-enclaves-sdk-c library, and calling KMS from the enclave. Enclave images without the library, or without kmstool-enclave for the first issue, are not affected by that issue.
No product ranges from the sources yet.
<= v0.4.5 are affected.v0.4.6 and rebuild enclave images that consume the library.Each row is the first time that source carried this signal. The analyst’s rows are its own findings.
CVE-2026-119116 and CVE-2026-119148 - Issues in AWS Nitro Enclaves SDK for C
Bulletin ID: 2026-157-AWS Scope: AWS Content Type: Important (requires attention) Publication Date: 10/30/2026 09:00 AM PDT
Description:
The AWS Nitro Enclaves SDK for C (aws-nitro-enclaves-sdk-c) is a library and set of example tools, including kmstool-enclave, for building applications that run inside AWS Nitro Enclaves and call AWS KMS using cryptographic attestation.
We identified CVE-2026-119116, a use-after-free in the SetClient command handler of the kmstool-enclave example application, where an application that executes on the parent EC2 instance could send crafted messages over vsock to corrupt heap memory inside the enclave and execute arbitrary code within it. Only enclave images that include kmstool-enclave, or code derived from it, are affected.
We also identified CVE-2026-119148, an input validation issue in the SDK library where the AWS KMS server name is built from a caller-supplied region string. A third party could supply a crafted region to impersonate KMS to the enclave and inject forged responses, such as actor-chosen key material.
Impacted versions: aws-nitro-enclaves-sdk-c <= v0.4.5 (CVE-2026-119116 affects kmstool-enclave only; CVE-2026-119148 affects the library)
Resolution:
Both issues have been addressed in aws-nitro-enclaves-sdk-c version v0.4.6. Customers who build enclave images which consume the aws-nitro-enclaves-sdk-c library should upgrade it to v0.4.6 and rebuild their enclave images.
Workarounds:
There are no workarounds. Upgrading is required.
References:
Acknowledgement:
We would like to thank Trail of Bits for reporting CVE-2026-119116 and collaborating on this issue through the coordinated vulnerability disclosure process.
Please email [email protected] with any security questions or concerns.
This page as .md · .json · in your agent: get_signal("CVE-2026-119148")
NVD data is provided by NIST and is public domain. Posts quoted belong to their authors.