CVE-2026-8596 json
Cleartext storage of HMAC signing key in Amazon SageMaker Python SDK ModelBuilder/Serve path
published 5mo ago modified 16d ago also EUVD-2026-30420 , GHSA-7hh5-prp2-mfh5 , PYSEC-2026-3059
- cvss
- 7.2
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.6%
- EPSS 0.6% chance of exploitation in 30 days, percentile 49%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- pypi sagemaker 2.257.2, 3.8.0
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 5mo ago
Exploit prediction
0.61% chance of exploitation in the next 30 days, higher than 49% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.2 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H |
| CNA | 4.0 | 8.5 | 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 |
| GitHub | 3.1 | 7.2 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H |
| CNA | 4.0 | 8.5 | 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 |
| OSV | 3.1 | 7.2 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | sagemaker | >=2.199.0, <2.257.2 >=3.0.0, <3.8.0 |
2.257.2 3.8.0 |
Affected products
- AWS Amazon SageMaker Python SDK
Classification
- Weakness
-
- CWE-312 Cleartext Storage of Sensitive Information
References
-
github.com
/aws/sagemaker-python-sdk/releases/tag/v2.257.2
patch, web
-
github.com
/aws/sagemaker-python-sdk/releases/tag/v3.8.0
patch, web
-
aws.amazon.com
/security/security-bulletins/2026-031-aws/
vendor-advisory
-
github.com
/aws/sagemaker-python-sdk/security/advisories/GHSA-7hh5-prp2-mfh5
third-party-advisory, web, advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-8596
advisory
-
aws.amazon.com
/security/security-bulletins/2026-031-aws
web
-
github.com
/aws/sagemaker-python-sdk
package
-
pypi.org
/project/sagemaker
package
-
github.com
/advisories/GHSA-7hh5-prp2-mfh5
advisory
Sources
- CVE List CVE-2026-8596
- GitHub Advisory GHSA-7hh5-prp2-mfh5
- NVD CVE-2026-8596
- OSV PYSEC-2026-3059
- Maintainer advisory GHSA-7hh5-prp2-mfh5
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
The maintainers of aws/sagemaker-python-sdk published their own advisory on GitHub. Reviewed sources take precedence over it.