URL Issues during logout - "Invalid nextUrl parameter"

Versions (relevant - OpenSearch/Dashboard/Server OS/Browser):
chart-version: 2.20.0
app-version: 2.16.0

Tested on:
Chrome: Version 128.0.6613.84 (Official Build) (64-bit)
Firefox: 129.0.2 (64-bit)
MS Edge: Version 128.0.2739.54 (Official build) (64-bit)

Describe the issue:
I’ve setup up Opensearch + Dashboards + FluentBit. I’ve configure basePath to /opensearch to expose dashboards there. Everything works great except the fact that when I press “logout”, instead of redirecting to the home screen, I am redirected to:
/opensearch/app/login?nextUrl=%2Fopensearch

with the following error:

{"statusCode":400,"error":"Bad Request","message":"[request query.nextUrl]: Invalid nextUrl parameter."}

What’s important is that I am getting logged out correctly, because if I manually go to /opensearch I got correctly redirected to /opensearch/app/login? and login screen is displayed. It was also confirmed in the logs:

message: POST /auth/<mark>logout</mark>?dataSourceId= 200 3ms - 9.0B

I tried setting rewriteBasePath to true, but it didn’t work (maybe I didn’t understood the setting correctly, nevertheless after setting it to true I couldn’t access it at all, so I commented it out as it was in the beginning.

Any help will be greatly appreciated.

Configuration:
values.yaml configuration (I only changed the resources and added Emissary ingress service annotations):

resources:
  requests:
    cpu: "100m"
    memory: "512M"
  limits:
    cpu: "300m"
    memory: "512M"

service:
  annotations:
    getambassador.io/config: |
      ---
      apiVersion: getambassador.io/v2
      kind: Mapping
      name: mapping-opensearch
      namespace: opensearch
      service: opensearch-dashboards:5601
      prefix: /opensearch/
      host: <host>
      bypass_auth: true
      timeout_ms: 30000
      ---
      apiVersion: getambassador.io/v2
      kind: Mapping
      name: mapping-opensearch-redirect
      namespace: opensearch
      service: <host>
      prefix: /opensearch
      bypass_auth: true
      host_redirect: true
      prefix_regex: true
      path_redirect: /opensearch/

opensearch-dashboards.yaml (I am only adding parts that are not commented out)

   # This setting cannot end in a slash.
   server.basePath: "/opensearch"
   opensearch.hosts: <default localhost setting> (new users can post only two URLs) 
   opensearch.ssl.verificationMode: none
   opensearch.username: kibanaserver
   opensearch.password: kibanaserver
   opensearch.requestHeadersWhitelist: [authorization, securitytenant]

   opensearch_security.multitenancy.enabled: true
   opensearch_security.multitenancy.tenants.preferred: [Private, Global]
   opensearch_security.readonly_mode.roles: [kibana_read_only]
   # Use this setting if you are running opensearch-dashboards without https
   opensearch_security.cookie.secure: false
   server.host: '0.0.0.0'

Relevant Logs or Screenshots:

@sichuanpepper What is the authentication type? Could you share your config.yml?

If by config.yaml you mean opensearch.yaml. Here it is (directly from the cm):

opensearch.yml:
----
cluster.name: opensearch-cluster

# Bind to all interfaces because we don't know what IP address Docker will assign to us.
network.host: 0.0.0.0

# Setting network.host to a non-loopback address enables the annoying bootstrap checks. "Single-node" mode disables them again.
# Implicitly done if ".singleNode" is set to "true".
# discovery.type: single-node

# Start OpenSearch Security Demo Configuration
# WARNING: revise all the lines below before you go into production
plugins:
  security:
    ssl:
      transport:
        pemcert_filepath: esnode.pem
        pemkey_filepath: esnode-key.pem
        pemtrustedcas_filepath: root-ca.pem
        enforce_hostname_verification: false
      http:
        enabled: true
        pemcert_filepath: esnode.pem
        pemkey_filepath: esnode-key.pem
        pemtrustedcas_filepath: root-ca.pem
    allow_unsafe_democertificates: true
    allow_default_init_securityindex: true
    authcz:
      admin_dn:
        - CN=kirk,OU=client,O=client,L=test,C=de
    audit.type: internal_opensearch
    enable_snapshot_restore_privilege: true
    check_snapshot_restore_write_privileges: true
    restapi:
      roles_enabled: ["all_access", "security_rest_api_access"]
    system_indices:
      enabled: true
      indices:
        [
          ".opendistro-alerting-config",
          ".opendistro-alerting-alert*",
          ".opendistro-anomaly-results*",
          ".opendistro-anomaly-detector*",
          ".opendistro-anomaly-checkpoints",
          ".opendistro-anomaly-detection-state",
          ".opendistro-reports-*",
          ".opendistro-notifications-*",
          ".opendistro-notebooks",
          ".opendistro-asynchronous-search-response*",
        ]
######## End OpenSearch Security Demo Configuration ########

If you had something else on your mind, could you please specify?

@sichuanpepper I meant config.yml. This is a basic security plugin configuration file.

Thank you for the clarification. FYI, we are still in the very early stage of implementing opensearch, thus we didn’t configure anything regarding security (as you might have guessed from the previous, default file). Here’s the config:

[opensearch@opensearch-cluster-master-0 ~]$ cat /usr/share/opensearch/config/opensearch-security/config.yml
---

# This is the main OpenSearch Security configuration file where authentication
# and authorization is defined.
#
# You need to configure at least one authentication domain in the authc of this file.
# An authentication domain is responsible for extracting the user credentials from
# the request and for validating them against an authentication backend like Active Directory for example.
#
# If more than one authentication domain is configured the first one which succeeds wins.
# If all authentication domains fail then the request is unauthenticated.
# In this case an exception is thrown and/or the HTTP status is set to 401.
#
# After authentication authorization (authz) will be applied. There can be zero or more authorizers which collect
# the roles from a given backend for the authenticated user.
#
# Both, authc and auth can be enabled/disabled separately for REST and TRANSPORT layer. Default is true for both.
#        http_enabled: true
#        transport_enabled: true
#
# For HTTP it is possible to allow anonymous authentication. If that is the case then the HTTP authenticators try to
# find user credentials in the HTTP request. If credentials are found then the user gets regularly authenticated.
# If none can be found the user will be authenticated as an "anonymous" user. This user has always the username "anonymous"
# and one role named "anonymous_backendrole".
# If you enable anonymous authentication all HTTP authenticators will not challenge.
#
#
# Note: If you define more than one HTTP authenticators make sure to put non-challenging authenticators like "proxy" or "clientcert"
# first and the challenging one last.
# Because it's not possible to challenge a client with two different authentication methods (for example
# Kerberos and Basic) only one can have the challenge flag set to true. You can cope with this situation
# by using pre-authentication, e.g. sending a HTTP Basic authentication header in the request.
#
# Default value of the challenge flag is true.
#
#
# HTTP
#   basic (challenging)
#   proxy (not challenging, needs xff)
#   kerberos (challenging)
#   clientcert (not challenging, needs https)
#   jwt (not challenging)
#   host (not challenging) #DEPRECATED, will be removed in a future version.
#                          host based authentication is configurable in roles_mapping

# Authc
#   internal
#   noop
#   ldap

# Authz
#   ldap
#   noop



_meta:
  type: "config"
  config_version: 2

config:
  dynamic:
    # Set filtered_alias_mode to 'disallow' to forbid more than 2 filtered aliases per index
    # Set filtered_alias_mode to 'warn' to allow more than 2 filtered aliases per index but warns about it (default)
    # Set filtered_alias_mode to 'nowarn' to allow more than 2 filtered aliases per index silently
    #filtered_alias_mode: warn
    #do_not_fail_on_forbidden: false
    #kibana:
    # Kibana multitenancy
    #multitenancy_enabled: true
    #private_tenant_enabled: true
    #default_tenant: ""
    #server_username: kibanaserver
    #index: '.kibana'
    http:
      anonymous_auth_enabled: false
      xff:
        enabled: false
        internalProxies: '192\.168\.0\.10|192\.168\.0\.11' # regex pattern
        #internalProxies: '.*' # trust all internal proxies, regex pattern
        #remoteIpHeader:  'x-forwarded-for'
        ###### see https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html for regex help
        ###### more information about XFF https://en.wikipedia.org/wiki/X-Forwarded-For
        ###### and here https://tools.ietf.org/html/rfc7239
        ###### and https://tomcat.apache.org/tomcat-8.0-doc/config/valve.html#Remote_IP_Valve
    authc:
      kerberos_auth_domain:
        http_enabled: false
        transport_enabled: false
        order: 6
        http_authenticator:
          type: kerberos
          challenge: true
          config:
            # If true a lot of kerberos/security related debugging output will be logged to standard out
            krb_debug: false
            # If true then the realm will be stripped from the user name
            strip_realm_from_principal: true
        authentication_backend:
          type: noop
      basic_internal_auth_domain:
        description: "Authenticate via HTTP Basic against internal users database"
        http_enabled: true
        transport_enabled: true
        order: 4
        http_authenticator:
          type: basic
          challenge: true
        authentication_backend:
          type: intern
      proxy_auth_domain:
        description: "Authenticate via proxy"
        http_enabled: false
        transport_enabled: false
        order: 3
        http_authenticator:
          type: proxy
          challenge: false
          config:
            user_header: "x-proxy-user"
            roles_header: "x-proxy-roles"
        authentication_backend:
          type: noop
      jwt_auth_domain:
        description: "Authenticate via Json Web Token"
        http_enabled: false
        transport_enabled: false
        order: 0
        http_authenticator:
          type: jwt
          challenge: false
          config:
            signing_key: "base64 encoded HMAC key or public RSA/ECDSA pem key"
            jwt_header: "Authorization"
            jwt_url_parameter: null
            jwt_clock_skew_tolerance_seconds: 30
            roles_key: null
            subject_key: null
        authentication_backend:
          type: noop
      clientcert_auth_domain:
        description: "Authenticate via SSL client certificates"
        http_enabled: false
        transport_enabled: false
        order: 2
        http_authenticator:
          type: clientcert
          config:
            username_attribute: cn #optional, if omitted DN becomes username
          challenge: false
        authentication_backend:
          type: noop
      ldap:
        description: "Authenticate via LDAP or Active Directory"
        http_enabled: false
        transport_enabled: false
        order: 5
        http_authenticator:
          type: basic
          challenge: false
        authentication_backend:
          # LDAP authentication backend (authenticate users against a LDAP or Active Directory)
          type: ldap
          config:
            # enable ldaps
            enable_ssl: false
            # enable start tls, enable_ssl should be false
            enable_start_tls: false
            # send client certificate
            enable_ssl_client_auth: false
            # verify ldap hostname
            verify_hostnames: true
            hosts:
            - localhost:8389
            bind_dn: null
            password: null
            userbase: 'ou=people,dc=example,dc=com'
            # Filter to search for users (currently in the whole subtree beneath userbase)
            # {0} is substituted with the username
            usersearch: '(sAMAccountName={0})'
            # Use this attribute from the user as username (if not set then DN is used)
            username_attribute: null
    authz:
      roles_from_myldap:
        description: "Authorize via LDAP or Active Directory"
        http_enabled: false
        transport_enabled: false
        authorization_backend:
          # LDAP authorization backend (gather roles from a LDAP or Active Directory, you have to configure the above LDAP authentication backend settings too)
          type: ldap
          config:
            # enable ldaps
            enable_ssl: false
            # enable start tls, enable_ssl should be false
            enable_start_tls: false
            # send client certificate
            enable_ssl_client_auth: false
            # verify ldap hostname
            verify_hostnames: true
            hosts:
            - localhost:8389
            bind_dn: null
            password: null
            rolebase: 'ou=groups,dc=example,dc=com'
            # Filter to search for roles (currently in the whole subtree beneath rolebase)
            # {0} is substituted with the DN of the user
            # {1} is substituted with the username
            # {2} is substituted with an attribute value from user's directory entry, of the authenticated user. Use userroleattribute to specify the name of the attribute
            rolesearch: '(member={0})'
            # Specify the name of the attribute which value should be substituted with {2} above
            userroleattribute: null
            # Roles as an attribute of the user entry
            userrolename: disabled
            #userrolename: memberOf
            # The attribute in a role entry containing the name of that role, Default is "name".
            # Can also be "dn" to use the full DN as rolename.
            rolename: cn
            # Resolve nested roles transitive (roles which are members of other roles and so on ...)
            resolve_nested_roles: true
            userbase: 'ou=people,dc=example,dc=com'
            # Filter to search for users (currently in the whole subtree beneath userbase)
            # {0} is substituted with the username
            usersearch: '(uid={0})'
            # Skip users matching a user name, a wildcard or a regex pattern
            #skip_users:
            #  - 'cn=Michael Jackson,ou*people,o=TEST'
            #  - '/\S*/'
      roles_from_another_ldap:
        description: "Authorize via another Active Directory"
        http_enabled: false
        transport_enabled: false
        authorization_backend:
          type: ldap
          #config goes here ...
  #    auth_failure_listeners:
  #      ip_rate_limiting:
  #        type: ip
  #        allowed_tries: 10
  #        time_window_seconds: 3600
  #        block_expiry_seconds: 600
  #        max_blocked_clients: 100000
  #        max_tracked_clients: 100000
  #      internal_authentication_backend_limiting:
  #        type: username
  #        authentication_backend: intern
  #        allowed_tries: 10
  #        time_window_seconds: 3600
  #        block_expiry_seconds: 600
  #        max_blocked_clients: 100000
  #        max_tracked_clients: 100000