CVE-2026-39910Network attack vector

Organization compromise via unauthorized service account attachment

Published Jun 8, 2026 · Updated Jun 8, 2026

Missing authorization in STACKIT IaaS API before 2026-05-28 allows remote authenticated users to compromise an organization. The PUT servers service-accounts endpoint fails to verify that the requested service account belongs to the caller's tenant before attaching it to a controlled VM. Low-privileged access and control of a VM are required; the attached account's OAuth2 token is then exposed through the server-local metadata API, granting that account's organization-wide permissions.

CVSS severity8.7
High
EPSS probability0.26%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Missing authorization in STACKIT IaaS API before 2026-05-28 allows remote authenticated users to compromise an organization. The PUT servers service-accounts endpoint fails to verify that the requested service account belongs to the caller's tenant before attaching it to a controlled VM. Low-privileged access and control of a VM are required; the attached account's OAuth2 token is then exposed through the server-local metadata API, granting that account's organization-wide permissions.

The record

CVE
CVE-2026-39910
Published
Jun 8, 2026
Updated
Jun 8, 2026
Vendor
STACKIT
Product
IaaS API
Classifications
CWE-862, T1528
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 8, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 8, 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.

  1. Affected versionversion=0 <2026-05-28

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

STACKIT · IaaS APIversion=0 <2026-05-28

Published CVSS scores

8.7VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
8.8VulnCheckCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-862Missing Authorization
T1528Steal Application Access Token

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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