CVE-2026-17107Network attack vector

Cluster-admin escalation via impersonation header injection

Published Jul 24, 2026 · Updated Aug 25, 2026

Privilege escalation in Red Hat multicluster engine for Kubernetes allows remote authenticated users to gain cluster-admin via proxied requests. The cluster-proxy service-proxy appends impersonation group headers to forwarded requests without first stripping caller-supplied Impersonate-Group values, so the spoke ServiceAccount proxies attacker-chosen groups with its unrestricted impersonation rights. Exploitation requires authenticated access to the ACM hub cluster and deliberate requests through cluster-proxy, but successful abuse grants administrative control on each managed cluster reached through the hub.

CVSS severity8.5
High
EPSS probability0.35%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Privilege escalation in Red Hat multicluster engine for Kubernetes allows remote authenticated users to gain cluster-admin via proxied requests. The cluster-proxy service-proxy appends impersonation group headers to forwarded requests without first stripping caller-supplied Impersonate-Group values, so the spoke ServiceAccount proxies attacker-chosen groups with its unrestricted impersonation rights. Exploitation requires authenticated access to the ACM hub cluster and deliberate requests through cluster-proxy, but successful abuse grants administrative control on each managed cluster reached through the hub.

The record

CVE
CVE-2026-17107
Published
Jul 24, 2026
Updated
Aug 25, 2026
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-441, T1068
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 24, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 25, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

8.5Red HatCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
8.5cve.orgCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/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-441Unintended Proxy or Intermediary ('Confused Deputy')
T1068Exploitation for Privilege Escalation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo