Executive brief
@hulumi/policies is a library that validates AWS IAM trust policies for security guardrails, particularly when using GitHub Actions OIDC authentication. Versions before 1.3.2 failed to properly inspect AWS set-qualified condition operators (like ForAnyValue:StringLike), allowing attackers to bypass critical security checks that prevent wildcard GitHub Actions subject claims in trust policies. This could allow unauthorized access to AWS resources when GitHub Actions workflows are misconfigured.
Technical details
The vulnerability is an improper access control flaw (CWE-284) in the AWS trust-policy inspection logic. The vulnerable code in @hulumi/policies versions before 1.3.2 only validated AWS IAM condition operators when using exact StringLike/StringEquals keys in the G_OIDC_1 guardrail, but failed to evaluate set-qualified operators (prefixed with "ForAnyValue:" or similar). This allows an attacker to craft IAM trust policies with unsafe GitHub OIDC subject conditions that evade the mandatory validation. The attack requires the ability to define or modify AWS IAM trust policies. Patch 1.3.2 fixes this by properly evaluating all set-qualified string operators and rejecting unsafe GitHub OIDC sub conditions.
Affected products
- hulumi @hulumi/policies < 1.3.2
Timeline
- 2026-05-21: disclosed: GitHub Security Advisory GHSA-q2f7-m237-v562 published
- 2026-05-21: patched: Version 1.3.2 released with fix