CVE-2026-39910

STACKIT IaaS API contains a missing authorization check vulnerability that allows authenticated, low-privileged attackers to escalate privileges to full organization compromise by attaching arbitrary service accounts to virtual machines they control. Attackers can exploit the unvalidated PUT servers service-accounts endpoint to attach high-privileged service accounts and query the Instance Metadata Service to retrieve OAuth2 tokens, bypassing tenant boundaries and gaining unauthorized control over the entire organization environment.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://status.stackit.cloud
https://www.vulncheck.com/advisories/stackit-iaas-api-privilege-escalation-via-service-account-attachment

Configurations

No configuration.

History

No history.

Information

Published : 2026-06-08 17:16

Updated : 2026-08-24 11:16

NVD link : CVE-2026-39910

Mitre link : CVE-2026-39910

CVE.ORG link : CVE-2026-39910

JSON object : View

Products Affected

No product.

CWE

CWE-862

Missing Authorization

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