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TI-2026-25810 Aliases CVE-2026-33413GHSA-q8m4-xhhv-38mg

etcd: Authorization bypasses in multiple APIs

Priority MEDIUM 44CWE-862Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Security bypass
Confidentiality · integrity · availability
Low · Low · High
Fix status
Partial Red Hat: 5 fixed, 2 without a fix

Attack profile from CVSS 4.0 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-862.

Summary

etcd is a distributed key-value store for the data of a distributed system. Prior to versions 3.4.42, 3.5.28, and 3.6.9, unauthorized users may bypass authentication or authorization checks and call certain etcd functions in clusters that expose the gRPC API to untrusted or partially trusted clients. In unpatched etcd clusters with etcd auth enabled, unauthorized users are able to call MemberList and learn cluster topology, including member IDs and advertised endpoints; call Alarm, which can be abused for operational disruption or denial of service; use Lease APIs, interfering with TTL-based keys and lease ownership; and/or trigger compaction, permanently removing historical revisions and disrupting watch, audit, and recovery workflows. Kubernetes does not rely on etcd’s built-in authentication and authorization. Instead, the API server handles authentication and authorization itself, so typical Kubernetes deployments are not affected. Versions 3.4.42, 3.5.28, and 3.6.9 contain a patch. If upgrading is not immediately possible, reduce exposure by treating the affected RPCs as unauthenticated in practice. Restrict network access to etcd server ports so only trusted components can connect and/or require strong client identity at the transport layer, such as mTLS with tightly scoped client certificate distribution.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00258 17th percentileScored 2026-11-07
Fix Partial etcd (etcd-io): 3.6.9, 3.5.28, 3.4.42go.etcd.io/etcd/v3 (Go): 3.6.9, 3.5.28, 3.4.42Red Hat: 5 advisoriesRed Hat: 5 fixed, 2 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
etcd-ioetcd3.6.0-alpha.0 to before 3.6.9; 3.5.0-alpha.0 to before 3.5.28; before 3.4.423.6.9, 3.5.28, 3.4.42Patch availableCNA
—go.etcd.io/etcd/v3 (Go)3.6.0-alpha.0 to before 3.6.93.6.9Patch availableGHSA-q8m4-xhhv-38mg
—go.etcd.io/etcd/v3 (Go)3.5.0-alpha.0 to before 3.5.283.5.28Patch availableGHSA-q8m4-xhhv-38mg
—go.etcd.io/etcd/v3 (Go)before 3.4.423.4.42Patch availableGHSA-q8m4-xhhv-38mg
—go.etcd.io/etcd (Go)up to 3.3.27—No fix listedGHSA-q8m4-xhhv-38mg
  • etcd Vendoretcd-io Affected 3.6.0-alpha.0 to before 3.6.9; 3.5.0-alpha.0 to before 3.5.28; before 3.4.42 Fixed in 3.6.9, 3.5.28, 3.4.42 Patch available CNA
  • go.etcd.io/etcd/v3 (Go) Vendor— Affected 3.6.0-alpha.0 to before 3.6.9 Fixed in 3.6.9 Patch available GHSA-q8m4-xhhv-38mg
  • go.etcd.io/etcd/v3 (Go) Vendor— Affected 3.5.0-alpha.0 to before 3.5.28 Fixed in 3.5.28 Patch available GHSA-q8m4-xhhv-38mg
  • go.etcd.io/etcd/v3 (Go) Vendor— Affected before 3.4.42 Fixed in 3.4.42 Patch available GHSA-q8m4-xhhv-38mg
  • go.etcd.io/etcd (Go) Vendor— Affected up to 3.3.27 Fixed in — No fix listed GHSA-q8m4-xhhv-38mg

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:etcd:etcd:*:*:*:*:*:*:*:*before 3.4.42; 3.5.0 to before 3.5.28; 3.6.0 to before 3.6.9Vulnerableetcd-io
  • cpe:2.3:a:etcd:etcd:*:*:*:*:*:*:*:* Versions before 3.4.42; 3.5.0 to before 3.5.28; 3.6.0 to before 3.6.9 Vulnerable ·etcd-io

Remediation

  • Fix · CNA etcd (etcd-io) Fixed in 3.6.9, 3.5.28, 3.4.42
  • Fix · GHSA-q8m4-xhhv-38mg go.etcd.io/etcd/v3 (Go) Fixed in 3.6.9 Advisory →
  • Fix · GHSA-q8m4-xhhv-38mg go.etcd.io/etcd/v3 (Go) Fixed in 3.5.28 Advisory →
  • Fix · GHSA-q8m4-xhhv-38mg go.etcd.io/etcd/v3 (Go) Fixed in 3.4.42 Advisory →

Red Hat 5 advisories

  • RHSA-2026:54757 Released 2026-08-13 · Red Hat rating Important
    Red Hat OpenStack Platform 16.2 security advisory
    • Red Hat OpenStack Platform 16.2 collectd-sensubility-0.2.1-1.1.el8ost, erlang-23.3.4.18-2.el8ost, erlang-asn1-23.3.4.18-2.el8ost +41
  • RHSA-2026:28047 Released 2026-06-22 · Red Hat rating Important
    Red Hat OpenStack Platform 17.1 (etcd) security update
    • Red Hat OpenStack Platform 17.1 etcd-3.4.26-9.5.el9ost
  • RHSA-2026:23345 Released 2026-06-04 · Red Hat rating Important
    Multicluster Global Hub 1.6.2 security update
    • Multicluster Global Hub 1.6.6 registry.redhat.io/multicluster-globalhub/multicluster-globalhub-agent-rhel9, registry.redhat.io/multicluster-globalhub/multicluster-globalhub-grafana-rhel9, registry.redhat.io/multicluster-globalhub/multicluster-globalhub-manager-rhel9 +1
Show 2 more Red Hat advisories
  • RHSA-2026:22347 Released 2026-06-01 · Red Hat rating Important
    Multicluster Global Hub 1.4.5 security update
    • Multicluster Global Hub 1.4.9 registry.redhat.io/multicluster-globalhub/multicluster-globalhub-agent-rhel9, registry.redhat.io/multicluster-globalhub/multicluster-globalhub-grafana-rhel9, registry.redhat.io/multicluster-globalhub/multicluster-globalhub-manager-rhel9 +1
  • RHSA-2026:21769 Released 2026-05-28 · Red Hat rating Important
    Multicluster Global Hub 1.5.4 security update
    • Multicluster Global Hub 1.5.8 registry.redhat.io/multicluster-globalhub/multicluster-globalhub-agent-rhel9, registry.redhat.io/multicluster-globalhub/multicluster-globalhub-grafana-rhel9, registry.redhat.io/multicluster-globalhub/multicluster-globalhub-manager-rhel9 +1

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
OpenShift Service Mesh 2AffectedNo fix yet
Red Hat OpenShift GitOpsAffectedNo fix yet
Multicluster Global Hub 1.4.9Fixed RHSA-2026:22347
Multicluster Global Hub 1.5.8Fixed RHSA-2026:21769
Multicluster Global Hub 1.6.6Fixed RHSA-2026:23345
Red Hat OpenStack Platform 16.2Fixed RHSA-2026:54757
Red Hat OpenStack Platform 17.1Fixed RHSA-2026:28047
Not affected: 7 products
  • Multicluster Global Hub 1.4.9
  • Multicluster Global Hub 1.5.8
  • Multicluster Global Hub 1.6.6
  • Red Hat Ansible Automation Platform 2
  • Red Hat OpenShift Container Platform 4
  • Red Hat OpenStack Platform 16.2
  • Red Hat OpenStack Platform 18.0

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-33413
  2. 2026-10-03 Alias added: GHSA-q8m4-xhhv-38mg

References

Advisory 2

Other 1

  • TI-2021-09444 Authentication vulnerability found in Etcd-io v.3.4.10 allows remote attackers to… CVSS 3.1CRITICAL 9.8
  • TI-2022-15016 Etcd v3.5.4 allows remote attackers to cause a denial of service via function… CVSS 3.1HIGH 7.5
  • TI-2018-12096 Improper authentication in etcd: CVSS 3.1HIGH 8.1
  • TI-2026-42635 etcd: gRPC client listener does not enforce `--client-crl-file` certificate revocation CVSS 3.1HIGH 8.1
  • TI-2026-25749 etcd: Nested etcd transactions bypass RBAC authorization checks CVSS 3.1MEDIUM 6.5
  • TI-2020-11888 Improper Preservation of Permissions in etcd CVSS 3.1HIGH 7.1
See all 10 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences