CVE-2026-59818Public exploitNetwork attack vector

Authentication bypass via omitted gRPC CRL check

Published Jul 8, 2026 · Updated Jul 8, 2026

Certificate validation in etcd before 3.5.32 and 3.6.0-alpha.0 through 3.6.12 allows remote authenticated users to access gRPC. In server/embed/serve.go, gRPC-only mode passes a TLS configuration to grpc.Creds without attaching the CRL check used by the combined listener. Exploitation requires split HTTP and gRPC listeners, an enabled client CRL, and a revoked certificate trusted by the cluster; successful access carries that certificate identity's data permissions.

CVSS severity8.1
High
EPSS probability0.43%
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

Certificate validation in etcd before 3.5.32 and 3.6.0-alpha.0 through 3.6.12 allows remote authenticated users to access gRPC. In server/embed/serve.go, gRPC-only mode passes a TLS configuration to grpc.Creds without attaching the CRL check used by the combined listener. Exploitation requires split HTTP and gRPC listeners, an enabled client CRL, and a revoked certificate trusted by the cluster; successful access carries that certificate identity's data permissions.

The record

CVE
CVE-2026-59818
Published
Jul 8, 2026
Updated
Jul 8, 2026
Vendor
etcd-io
Product
etcd
Classifications
CWE-295, T1078
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

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

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 3.5.32
  2. Affected versionversion=>= 3.6.0-alpha.0, < 3.6.13

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

etcd-io · etcdversion=< 3.5.32; version=>= 3.6.0-alpha.0, < 3.6.13

Published CVSS scores

8.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
6.5GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N

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 exploitPublished

Weakness, pattern, technique

CWE-295Improper Certificate Validation
T1078Valid Accounts

Public exploit references

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