Policy bypass via unbound hardening siblings
Published Jul 24, 2026 · Updated Jul 24, 2026
Access control bypass in Hulumi @hulumi/policies before 1.4.0 allows remote authenticated users to deploy unhardened S3 buckets. The HULUMI-H5 rule checks only for five sibling resource types and fails to bind each sibling's bucket reference or policy ARN to the exempted raw bucket. A consumer or compromised pull request with permission to change Pulumi code can make the hardening pack report compliance while omitting public-access blocking, SSE-KMS, ownership controls, versioning, and a TLS-only policy.
Summary
What happened
Access control bypass in Hulumi @hulumi/policies before 1.4.0 allows remote authenticated users to deploy unhardened S3 buckets. The HULUMI-H5 rule checks only for five sibling resource types and fails to bind each sibling's bucket reference or policy ARN to the exempted raw bucket. A consumer or compromised pull request with permission to change Pulumi code can make the hardening pack report compliance while omitting public-access blocking, SSE-KMS, ownership controls, versioning, and a TLS-only policy.
The record
- CVE
- CVE-2026-48034
- Published
- Jul 24, 2026
- Updated
- Jul 24, 2026
- Vendor
- Sherif Mansour
- Product
- Hulumi
- Classifications
- CWE-284, T1562.001
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 24, 2026CVE publishedPublication date reported by the CVE source.
- Jul 24, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=< 1.4.0
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- HULUMI-H5 decoy-sibling regression caseproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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