CVE-2026-48034 in hulumi
Summary
by MITRE • 07/24/2026
Hulumi is an open-source toolkit that ships secure-by-default cloud and platform infrastructure components for Pulumi. Prior to version 1.4.0, there is a bypass via decoy sibling resources targeting a different bucket. This issue has been patched in version 1.4.0.
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Analysis
by VulDB Data Team • 07/24/2026
The vulnerability in Hulumi toolkit represents a security bypass mechanism that exploits resource management patterns within the cloud infrastructure provisioning framework. This flaw specifically targets the handling of sibling resources and their relationship to storage buckets, creating an unintended pathway for privilege escalation or access control circumvention. The issue stems from how the system processes resource dependencies and validation checks when multiple related resources exist within the same deployment scope. Attackers could leverage this vulnerability by creating decoy sibling resources that appear to target one bucket while actually manipulating the system's behavior to affect a different bucket, thereby bypassing intended security controls.
The technical implementation of this vulnerability involves manipulating the resource dependency graph that Pulumi uses to manage infrastructure deployments. When Hulumi processes sibling resources, it fails to properly validate cross-referenced bucket permissions or access controls between related components. This allows an attacker to construct resource definitions where one component references a specific bucket while another component in the same resource group references a different bucket, creating a scenario where the system's validation logic becomes confused about which bucket should be subject to security checks. The flaw operates at the level of resource resolution and dependency management within the Pulumi deployment engine, specifically in how it handles cross-resource references during the planning phase.
The operational impact of this vulnerability extends beyond simple access control bypasses to potentially enable more serious security compromises within cloud infrastructure deployments. An attacker could exploit this weakness to gain unauthorized access to storage buckets that should otherwise be protected by security policies or access controls. This could lead to data exposure, privilege escalation, or the ability to modify or delete resources in ways that violate the intended security posture of the infrastructure. The vulnerability affects organizations using Hulumi for provisioning cloud resources, particularly those implementing secure-by-default configurations where bucket-level permissions are critical for maintaining data security boundaries.
Mitigation strategies for this vulnerability focus on updating to version 1.4.0 or later, which includes patched validation logic for resource dependencies and bucket access controls. Organizations should conduct thorough audits of their existing deployments to identify any configurations that might be susceptible to this bypass mechanism before applying the update. The fix addresses the core issue by strengthening the validation of sibling resource relationships and ensuring proper cross-referencing of bucket permissions during the deployment planning phase. Security teams should also implement monitoring for unusual resource creation patterns or unexpected bucket access requests that could indicate exploitation attempts. Additionally, organizations should review their Pulumi deployment configurations to ensure that resource dependencies are properly structured and that access controls are consistently applied across all related resources in the infrastructure stack.
This vulnerability aligns with CWE-284 Access Control Issues, specifically addressing improper access control mechanisms in resource management systems. The bypass pattern also relates to ATT&CK technique T1078 Valid Accounts, as it could enable attackers to operate under seemingly legitimate resource access patterns while circumventing security controls. The issue demonstrates the importance of proper resource validation in infrastructure-as-code tools and highlights how seemingly minor implementation flaws in dependency resolution can create significant security risks in cloud deployment environments. Organizations implementing secure-by-default infrastructure should pay particular attention to resource relationship validation and cross-checking mechanisms to prevent similar bypass scenarios from occurring in other components of their infrastructure provisioning pipeline.