hulumi CVE-2026-82859

Exploitation requires an AWS environment where hulumi's deployment SCP template (versions before v1.3.2) has been applied to protect the hulumi:iac-role, and an actor able to issue resource create/tag API calls within that organization. The concrete prerequisite is the tag-on-create evaluation in the SCP: the attacker sets the tag the policy keys on during the create request, satisfying the condition and bypassing the IAM boundary. Limiting factors: the vulnerable SCP template must actually be deployed (non-default to any given environment - only hulumi-managed AWS orgs are affected), and realistically the attacker needs an existing AWS principal with permission to create/tag resources, so the scored PR:N likely understates the required foothold.

The supplied CVSS 4.0 vector (AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H) yields a 9.3 Critical rating with high confidentiality, integrity, and availability impact and no privileges required. However, the nature of the flaw - bypassing an SCP guardrail on an IAM deployment role via tag-on-create - realistically presupposes that the attacker already holds some authenticated AWS principal capable of issuing create/tag API calls within the target organization, which is at odds with PR:N. This is a meaningful signal conflict: the scored vector treats it as unauthenticated network exploitation, but the described mechanism implies at least a low-privileged authenticated foothold - verify PR level with the vendor advisory. No EPSS score, KEV listing, or POC is provided, so there is no evidence of active or widespread exploitation; this is a design/guardrail-weakness class issue whose real-world priority is highest for organizations that actually deployed the vulnerable SCP template to protect privileged roles. Absent exploitation evidence, treat it as a high-priority hardening fix rather than an emergency in-the-wild threat.

An attacker who controls a low-privileged principal in an AWS organization governed by hulumi's vulnerable SCP template issues a resource-creation API call that attaches the specific tag the SCP checks for, satisfying the guardrail condition at create time. This lets them create or assume resources that the hulumi:iac-role boundary was meant to forbid, escalating effective privileges within the environment. No public POC has been identified, so exploitation would require an actor familiar with the SCP's tag-condition logic.