Security readout for executives and security teams
Plain-English summary
An authenticated user on the management hub could abuse trusted proxy behavior to gain cluster-admin privileges across every managed Kubernetes cluster. Successful exploitation could expose or alter workloads, secrets, and cluster configuration, or disrupt operations across the managed fleet.
Executive priority
Treat as an urgent fleet-wide privilege-escalation issue. Prioritize affected management hubs because one authenticated hub account could compromise every connected cluster. Patch promptly, restrict proxy access during remediation, and investigate suspicious impersonation activity; no active exploitation is established by the supplied evidence.
Technical view
Cluster-proxy service-proxy fails to remove caller-supplied Impersonate-Group headers before appending trusted groups. Because the spoke ServiceAccount has unrestricted impersonation permissions, an authenticated low-privileged hub principal can inject a group identity and escalate across managed clusters. The issue is classified as CWE-441 with CVSS 3.1 score 8.5.
Likely exposure
The bundle explicitly identifies multicluster engine 2.8, 2.9, and 2.10 cluster-proxy-rhel9 packages as affected. RHACM is also named, but affected RHACM versions are not enumerated. Exposure requires an authenticated hub principal able to send requests through service-proxy.
Exploitation context
The attack is network-accessible, requires low privileges and no user interaction, but has high attack complexity. Successful exploitation crosses security boundaries and can affect confidentiality, integrity, and availability. The bundle marks KEV as false and provides no evidence of active exploitation.
Researcher notes
The security failure combines trusted-proxy header handling with an overprivileged downstream identity. Scope changes from the hub principal to managed clusters, explaining the CVSS scope-change rating. The supplied records do not provide exploit telemetry, fixed package versions, or enough detail to determine every affected RHACM release.
Mitigation direction
- Identify deployments using the affected MCE cluster-proxy-rhel9 packages and prioritize internet- or broadly accessible hubs.
- Apply the applicable Red Hat security updates referenced by the four RHSA advisories.
- Consult Red Hat guidance for RHACM applicability because affected RHACM versions are not listed in the bundle.
- Until updated, restrict hub access and service-proxy use to essential, trusted principals.
- Review and minimize unrestricted impersonation permissions assigned to spoke ServiceAccounts, following vendor guidance.
Validation and detection
- Inventory MCE versions and cluster-proxy-rhel9 package builds across all management hubs.
- Confirm applicable Red Hat errata are installed using approved asset and patch-management records.
- Verify untrusted hub principals cannot supply or preserve impersonation group headers through service-proxy.
- Review hub proxy logs for unexpected Impersonate-Group headers or cluster-admin group identities.
- Audit spoke ServiceAccount impersonation permissions and investigate unexplained privileged activity on managed clusters.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-441: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupContainer behavior lookup
The affected technology mentions containers, so container-specific ATT&CK technique review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2026-17107 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 8.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
SSVC decision data
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H1.86redhatVulnerability scoring details
Base CVSS 3.1 score
8.5HighVector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- Source timelineredhat
Reported to Red Hat.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- Source timelineredhat
Made public.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- RHSA-2026:46885CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2026:47388CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2026:47735CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2026:47953CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/security/cve/CVE-2026-17107CVE reference, redhat · vdb-entry, x_refsource_REDHAT
- RHBZ#2506771CVE reference, redhat · issue-tracking, x_refsource_REDHAT
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Unintended Proxy or Intermediary ('Confused Deputy')
Unintended Proxy or Intermediary ('Confused Deputy') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.