Cleartext storage of HMAC signing key in Amazon SageMaker Python SDK ModelBuilder/Serve path
Summary
| CVE | CVE-2026-8596 |
|---|---|
| State | PUBLISHED |
| Assigner | AMZN |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-05-14 20:17:21 UTC |
| Updated | 2026-05-15 14:10:17 UTC |
| Description | Cleartext storage of sensitive information in the ModelBuilder/Serve component in Amazon SageMaker Python SDK before v2.257.2 and v3 before v3.8.0 might allow a remote authenticated actor to extract the HMAC signing key from SageMaker API responses and forge valid integrity signatures for specially crafted model artifacts, achieving code execution in inference containers. This issue requires a remote authenticated actor with permissions to call SageMaker describe APIs and S3 write access to the model artifact path. To remediate this issue, we recommend upgrading to Amazon SageMaker Python SDK v2.257.2 or v3.8.0 and rebuild any models previously created with ModelBuilder using the updated SDK. |
Risk And Classification
Primary CVSS: v4.0 8.5 HIGH from ff89ba41-3aa1-4d27-914a-91399e9639e5
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:N/VA:N/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS: 0.000550000 probability, percentile 0.171080000 (date 2026-05-25)
Problem Types: CWE-312 | CWE-312 CWE-312 Cleartext storage of sensitive information
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | ff89ba41-3aa1-4d27-914a-91399e9639e5 | Secondary | 8.5 | HIGH | CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:N/VA:N/SC:H/SI:H/SA:H/E:X/C... |
| 4.0 | CNA | CVSS | 8.5 | HIGH | CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:N/VA:N/SC:H/SI:H/SA:H |
| 3.1 | ff89ba41-3aa1-4d27-914a-91399e9639e5 | Secondary | 7.2 | HIGH | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H |
| 3.1 | CNA | CVSS | 7.2 | HIGH | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H |
CVSS v4.0 Breakdown
Attack Vector
NetworkAttack Complexity
LowAttack Requirements
NonePrivileges Required
HighUser Interaction
NoneConfidentiality
HighIntegrity
NoneAvailability
NoneSub Conf.
HighSub Integrity
HighSub Availability
HighCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:N/VA:N/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
HighUser Interaction
NoneScope
UnchangedConfidentiality
HighIntegrity
HighAvailability
HighCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Amazon SageMaker Python SDK | AWS | affected 2.199.0 2.257.1 custom | Not specified |
| CNA | Amazon SageMaker Python SDK | AWS | affected 3.0.0 3.7.1 custom | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| github.com/aws/sagemaker-python-sdk/releases/tag/v3.8.0 | ff89ba41-3aa1-4d27-914a-91399e9639e5 | github.com | |
| aws.amazon.com/security/security-bulletins/2026-031-aws | ff89ba41-3aa1-4d27-914a-91399e9639e5 | aws.amazon.com | |
| github.com/aws/sagemaker-python-sdk/security/advisories/GHSA-7hh5-prp2-mfh5 | ff89ba41-3aa1-4d27-914a-91399e9639e5 | github.com | |
| github.com/aws/sagemaker-python-sdk/releases/tag/v2.257.2 | ff89ba41-3aa1-4d27-914a-91399e9639e5 | github.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.