elasticsearch-security-troubleshooting

Elasticsearch Security Troubleshooting

Diagnose and resolve common Elasticsearch security issues. This skill provides a structured triage workflow for authentication failures, authorization errors, TLS problems, API key issues, role mapping mismatches, Kibana login failures, and license-expiry lockouts.

For authentication methods and API key management, see the elasticsearch-authn skill. For roles, users, and role mappings, see the elasticsearch-authz skill. For license management, see the elasticsearch-license skill.

For diagnostic API endpoints, see references/api-reference.md.

Deployment note: Diagnostic API availability differs between self-managed, ECH, and Serverless. See Deployment Compatibility for details.

Jobs to Be Done

• Diagnose HTTP 401 authentication failures
• Diagnose HTTP 403 permission denied errors
• Troubleshoot TLS/SSL handshake or certificate errors
• Investigate expired or invalid API keys
• Debug role mappings that do not grant expected roles
• Fix Kibana login failures, redirect loops, or CORS errors
• Recover from a license-expiry lockout
• Determine why a user lacks access to a specific index

Prerequisites

Item	Description
Elasticsearch URL	Cluster endpoint (e.g. https://localhost:9200 or a Cloud deployment URL)
Authentication	Any valid credentials — even minimal — to reach the cluster
Cluster privileges	monitor for read-only diagnostics; manage_security for fixes

Prompt the user for any missing values. If the user cannot authenticate at all, start with TLS and Certificate Errors or License Expiry Recovery.

Diagnostic Workflow

Route the symptom to the correct section:

Symptom	Section
HTTP 401, authentication_exception	Authentication Failures
HTTP 403, security_exception, access denied	Authorization Failures
SSL/TLS handshake error, certificate rejected	TLS and Certificate Errors
API key rejected, expired, or ineffective	API Key Issues
Role mapping not granting expected roles	Role Mapping Issues
Kibana login broken, redirect loop, CORS error	Kibana Authentication Issues
All users locked out, paid features disabled	License Expiry Recovery

Each section follows a Gather - Diagnose - Resolve pattern.

Diagnostic Toolkit

Use these APIs at the start of any security investigation:

curl <auth_flags> "${ELASTICSEARCH_URL}/_security/_authenticate"

Confirms identity, realm, and roles. If this fails with 401, the problem is authentication.

curl <auth_flags> "${ELASTICSEARCH_URL}/_xpack"

Confirms whether security is enabled (features.security.enabled). If security is disabled, all security APIs return errors.

curl -X POST "${ELASTICSEARCH_URL}/_security/user/_has_privileges" \
  <auth_flags> \
  -H "Content-Type: application/json" \
  -d '{
    "index": [
      { "names": ["'"${INDEX_PATTERN}"'"], "privileges": ["read"] }
    ]
  }'

Tests whether the authenticated user holds specific privileges without requiring manage_security.

curl <auth_flags> "${ELASTICSEARCH_URL}/_license"

Check license type and status. An expired paid license disables paid realms and features.

Authentication Failures (401)

A 401 response means Elasticsearch could not verify the caller's identity.

Gather

curl -v <auth_flags> "${ELASTICSEARCH_URL}/_security/_authenticate" 2>&1

The -v flag shows headers and the response body. Look for:

• WWW-Authenticate header — indicates which auth schemes the cluster accepts.
• authentication_exception in the response body — the reason field describes what failed.

Diagnose

Symptom	Likely cause
unable to authenticate user	Wrong username or password
unable to authenticate with provided credentials	Credentials do not match any realm in the chain
user is not enabled	The native user account is disabled
token is expired	API key or bearer token has expired
No WWW-Authenticate header	Security may be disabled; check GET /_xpack

If the user authenticates via an external realm (LDAP, AD, SAML, OIDC), the realm chain order matters. Elasticsearch tries realms in configured order and stops at the first match. If a higher-priority realm rejects the credentials before the intended realm is reached, authentication fails.

Resolve

Cause	Action
Wrong credentials	Verify username/password or API key value. See elasticsearch-authn.
Disabled user	PUT /_security/user/{name}/_enable. See elasticsearch-authz.
Expired API key	Create a new API key. See API Key Issues.
Realm chain order	Check elasticsearch.yml realm order (self-managed only).
Security disabled	Enable xpack.security.enabled: true in elasticsearch.yml and restart.
Paid realm after expiry	License expired — see License Expiry Recovery.

Authorization Failures (403)

A 403 response means the user is authenticated but lacks the required privileges.

Gather

Test the specific privileges the operation requires:

curl -X POST "${ELASTICSEARCH_URL}/_security/user/_has_privileges" \
  <auth_flags> \
  -H "Content-Type: application/json" \
  -d '{
    "index": [
      { "names": ["logs-*"], "privileges": ["read", "view_index_metadata"] }
    ],
    "cluster": ["monitor"]
  }'

The response contains a has_all_requested boolean and per-resource breakdowns.

Also check the user's effective roles:

curl <auth_flags> "${ELASTICSEARCH_URL}/_security/_authenticate"

Inspect the roles array and authentication_realm to confirm the user is who you expect.

Diagnose

Symptom	Likely cause
has_all_requested: false for an index	Role is missing the required index privilege
has_all_requested: false for a cluster	Role is missing the required cluster privilege
User has fewer roles than expected	Roles array was replaced (not merged) on last update
API key returns 403 on previously allowed	API key privileges are a snapshot — role changes after
operation	creation do not propagate to existing keys

Resolve

Cause	Action
Missing index privilege	Add the privilege to the role or create a new role. See elasticsearch-authz.
Missing cluster privilege	Add the cluster privilege. See elasticsearch-authz.
Roles replaced on update	Fetch current roles first, then update with the full array. See elasticsearch-authz.
Stale API key privileges	Create a new API key with updated role_descriptors. See elasticsearch-authn.

TLS and Certificate Errors

TLS errors prevent the client from establishing a connection at all.

Gather

curl -v --cacert "${CA_CERT}" "https://${ELASTICSEARCH_HOST}:9200/" 2>&1 | head -30

Look for:

• SSL certificate problem: unable to get local issuer certificate — CA not trusted.
• SSL certificate problem: certificate has expired — certificate past its validity date.
• SSL: no alternative certificate subject name matches target host name — hostname mismatch.

For deeper inspection (self-managed only):

openssl s_client -connect "${ELASTICSEARCH_HOST}:9200" -showcerts </dev/null 2>&1

This displays the full certificate chain, expiry dates, and subject alternative names.

Diagnose

Error message	Likely cause
unable to get local issuer certificate	Missing or wrong CA certificate
certificate has expired	Server or CA certificate past expiry
no alternative certificate subject name matches	Certificate SAN does not include the hostname
self-signed certificate	Self-signed cert not in the trust store
SSLHandshakeException (Java client)	Truststore missing the CA or wrong password

Resolve

Cause	Action
Wrong CA cert	Pass the correct CA with --cacert or add it to the system trust store.
Expired certificate	Regenerate certificates with elasticsearch-certutil (self-managed).
Hostname mismatch	Regenerate the certificate with the correct SAN entries.
Self-signed cert	Distribute the CA cert to all clients or use a publicly trusted CA.
Quick workaround	Use curl -k / --insecure to skip verification. Not for production.

On ECH, TLS is managed by Elastic — certificate errors usually indicate the client is not using the correct Cloud endpoint URL. On Serverless, TLS is fully managed and transparent.

API Key Issues

Gather

Retrieve the key's metadata:

curl "${ELASTICSEARCH_URL}/_security/api_key?name=${KEY_NAME}" <auth_flags>

Check expiration, invalidated, and role_descriptors in the response.

Diagnose

Symptom	Likely cause
401 when using the key	Key expired or invalidated
403 on operations that should be allowed	Key was created with insufficient role_descriptors
Derived key has no access	API key created another API key — derived keys have no privilege
Key works for some indices but not others	role_descriptors scope is too narrow

Resolve

Cause	Action
Expired key	Create a new key with appropriate expiration. See elasticsearch-authn.
Invalidated key	Create a new key. Invalidated keys cannot be reinstated.
Wrong scope	Create a new key with correct role_descriptors. See elasticsearch-authn.
Derived key problem	Use POST /_security/api_key/grant with user credentials instead. See elasticsearch-authn.

Role Mapping Issues

Role mappings grant roles to users from external realms. When they fail silently, users authenticate but get no roles.

Gather

curl <auth_flags> "${ELASTICSEARCH_URL}/_security/_authenticate"

Note the username, authentication_realm.name, and roles array.

curl <auth_flags> "${ELASTICSEARCH_URL}/_security/role_mapping"

List all mappings and inspect their rules and enabled fields.

Diagnose

Symptom	Likely cause
User has empty roles array	No mapping matches the user's attributes
User gets wrong roles	A different mapping matched first or the rule is too broad
Mapping exists but does not apply	enabled is false
Mustache template produces wrong role name	Template syntax error or unexpected attribute value

Compare the user's authentication_realm.name and groups (from _authenticate) against each mapping's rules to find the mismatch.

Resolve

Cause	Action
No matching rule	Update the mapping rules to match the user's realm and attributes.
Mapping disabled	Set "enabled": true on the mapping.
Template error	Test the Mustache template with known attribute values. See elasticsearch-authz.
Rule too broad	Add all / except conditions to narrow the match. See elasticsearch-authz.

Kibana Authentication Issues

Missing kbn-xsrf header

All mutating Kibana API requests require the kbn-xsrf header:

curl -X PUT "${KIBANA_URL}/api/security/role/my-role" \
  <auth_flags> \
  -H "kbn-xsrf: true" \
  -H "Content-Type: application/json" \
  -d '{ ... }'

Without it, Kibana returns 400 Bad Request with "Request must contain a kbn-xsrf header".

SAML/OIDC redirect loop

Common causes:

• Incorrect xpack.security.authc.realms.saml.*.sp.acs or idp.metadata.path in elasticsearch.yml.
• Clock skew between the IdP and Elasticsearch nodes (SAML assertions have a validity window).
• Kibana server.publicBaseUrl does not match the SAML ACS URL.

Verify the SAML realm configuration:

curl <auth_flags> "${ELASTICSEARCH_URL}/_security/_authenticate"

If this returns a valid user via a non-SAML realm, the SAML realm itself is not being reached. Check realm chain order.

Kibana cannot reach Elasticsearch

Kibana logs Unable to retrieve version information from Elasticsearch nodes. Verify the elasticsearch.hosts setting in kibana.yml points to a reachable endpoint and the credentials (elasticsearch.username / elasticsearch.password or elasticsearch.serviceAccountToken) are valid.

License Expiry Recovery

When a paid license expires, the cluster enters a security-closed state: paid realms (SAML, LDAP, AD, PKI) stop working and users authenticating through them are locked out. Native and file realms remain functional.

Quick triage

curl <auth_flags> "${ELASTICSEARCH_URL}/_license"

If license.status is "expired", proceed with recovery.

Recovery steps

Follow the detailed recovery workflow in the elasticsearch-license skill. The critical first step depends on deployment type:

Deployment	First step
Self-managed	Log in with a file-based user (elasticsearch-users CLI) or native user.
ECH	Contact Elastic support or renew via the Cloud console.
Serverless	Not applicable — licensing is fully managed by Elastic.

Examples

User gets 403 when querying logs

Symptom: "I get a 403 when searching logs-*."

1. Verify identity:

curl -u "joe:${PASSWORD}" "${ELASTICSEARCH_URL}/_security/_authenticate"

Response shows "roles": ["viewer"].

1. Test privileges:

curl -X POST "${ELASTICSEARCH_URL}/_security/user/_has_privileges" \
  -u "joe:${PASSWORD}" \
  -H "Content-Type: application/json" \
  -d '{"index": [{"names": ["logs-*"], "privileges": ["read"]}]}'

Response: "has_all_requested": false — the viewer role does not include read on logs-*.

1. Fix: create a logs-reader role and assign it to Joe. See elasticsearch-authz.

API key stopped working

Symptom: "My API key returns 401 since yesterday."

1. Check the key:

curl -u "admin:${PASSWORD}" "${ELASTICSEARCH_URL}/_security/api_key?name=my-key"

Response shows "expiration": 1709251200000 — the key expired.

1. Fix: create a new API key with a suitable expiration. See elasticsearch-authn.

SAML login redirects to error

Symptom: "Clicking the SSO button in Kibana redirects to an error page."

1. Check if the SAML realm is reachable by authenticating with a non-SAML method:

curl -u "elastic:${PASSWORD}" "${ELASTICSEARCH_URL}/_security/_authenticate"

1. Verify the IdP metadata URL is accessible from the Elasticsearch nodes (self-managed):

curl -s "${IDP_METADATA_URL}" | head -5

1. Check for clock skew — SAML assertions are time-sensitive. Ensure NTP is configured on all nodes.
2. Verify server.publicBaseUrl in kibana.yml matches the SAML ACS URL configured in the IdP.

Users locked out after license expired

Symptom: "Nobody can log in to Kibana. We use SAML."

1. Check license:

curl -u "admin:${PASSWORD}" "${ELASTICSEARCH_URL}/_license"

Response shows "status": "expired", "type": "platinum".

1. The SAML realm is disabled because the paid license expired. Follow the recovery steps in elasticsearch-license: log in with a file-based or native user, then upload a renewed license or revert to basic.

Guidelines

Always start with _authenticate

Run GET /_security/_authenticate as the first diagnostic step. It reveals the user's identity, realm, roles, and authentication type in a single call. Most issues become apparent from this response alone.

Check the license early

Before investigating realm or privilege issues, verify the license is active with GET /_license. An expired paid license disables realms and features, producing symptoms that mimic misconfiguration.

Use _has_privileges before manual inspection

Instead of reading role definitions and mentally computing effective access, use POST /_security/user/_has_privileges to test specific privileges directly. This is faster and accounts for role composition, DLS, and FLS.

Avoid superuser credentials

Never use the built-in elastic superuser for day-to-day troubleshooting. Create a dedicated admin user or API key with manage_security privileges. Reserve the elastic user for initial setup and emergency recovery only.

Do not bypass TLS in production

Using curl -k or --insecure skips certificate verification and masks real TLS issues. Use it only for initial diagnosis, then fix the underlying certificate problem.

Deployment Compatibility

Diagnostic tool and API availability differs across deployment types.

Tool / API	Self-managed	ECH	Serverless
_security/_authenticate	Yes	Yes	Yes
_security/user/_has_privileges	Yes	Yes	Yes
_xpack	Yes	Yes	Limited
_license	Yes	Yes (read)	Not available
_security/api_key (GET)	Yes	Yes	Yes
_security/role_mapping	Yes	Yes	Yes
elasticsearch-users CLI	Yes	Not available	Not available
openssl s_client on nodes	Yes	Not available	Not available
Elasticsearch logs	Yes	Via Cloud UI	Via Cloud UI

ECH notes:

• No node-level access, so the elasticsearch-users CLI and direct log/certificate inspection are not available.
• TLS is managed by Elastic — certificate errors typically indicate an incorrect endpoint URL.
• Use the Cloud console for log inspection and deployment configuration.

Serverless notes:

• Licensing APIs are not exposed. License-related lockouts do not occur.
• Native users do not exist — authentication issues are handled at the organization level.
• TLS is fully managed and transparent.