[Bug]: Search users shows also disabled users

⚠️ This issue respects the following points: ⚠️

• This is a bug, not a question or a configuration/webserver/proxy issue.
• This issue is not already reported on Github OR Nextcloud Community Forum (I've searched it).
• Nextcloud Server is up to date. See Maintenance and Release Schedule for supported versions.
• I agree to follow Nextcloud's Code of Conduct.

Bug description

If you search a user, e.g. to

• share a file/directory
• invite to an event
• share a poll
• ...

there are also shown disabled users.

Since these users cannot handle the share/invitation, they should not be suggested in the search.

Steps to reproduce

1. add User 'willbedisabled'
2. Disable User 'willbedisabled'
3. go to a file and select share with
4. search e.g. 'will'
5. see the disabled user

Expected behavior

only active useres are suggested

Installation method

Community Manual installation with Archive

Nextcloud Server version

26

Operating system

Debian/Ubuntu

PHP engine version

PHP 8.1

Web server

Apache (supported)

Database engine version

MariaDB

Is this bug present after an update or on a fresh install?

Upgraded to a MAJOR version (ex. 22 to 23)

Are you using the Nextcloud Server Encryption module?

Encryption is Disabled

What user-backends are you using?

• Default user-backend (database)
• LDAP/ Active Directory
• SSO - SAML
• Other

Configuration report

{
    "system": {
        "filelocking.enabled": true,
        "memcache.local": "\\OC\\Memcache\\APCu",
        "memcache.distributed": "\\OC\\Memcache\\Redis",
        "memcache.locking": "\\OC\\Memcache\\Redis",
        "redis": {
            "host": "***REMOVED SENSITIVE VALUE***",
            "port": 6379
        },
        "instanceid": "***REMOVED SENSITIVE VALUE***",
        "passwordsalt": "***REMOVED SENSITIVE VALUE***",
        "secret": "***REMOVED SENSITIVE VALUE***",
        "trusted_domains": [
            "***REMOVED SENSITIVE VALUE***",
            "***REMOVED SENSITIVE VALUE***"
        ],
        "htaccess.RewriteBase": "\/",
        "datadirectory": "***REMOVED SENSITIVE VALUE***",
        "dbtype": "mysql",
        "version": "26.0.5.1",
        "overwrite.cli.url": "***REMOVED SENSITIVE VALUE***",
        "dbname": "***REMOVED SENSITIVE VALUE***",
        "dbhost": "***REMOVED SENSITIVE VALUE***",
        "dbport": "",
        "dbtableprefix": "oc_",
        "mysql.utf8mb4": true,
        "dbuser": "***REMOVED SENSITIVE VALUE***",
        "dbpassword": "***REMOVED SENSITIVE VALUE***",
        "installed": true,
        "updater.release.channel": "stable",
        "maintenance": false,
        "theme": "",
        "loglevel": 0,
        "mail_smtpmode": "smtp",
        "mail_smtpsecure": "tls",
        "mail_sendmailmode": "smtp",
        "mail_domain": "***REMOVED SENSITIVE VALUE***",
        "mail_smtphost": "***REMOVED SENSITIVE VALUE***",
        "mail_smtpport": "587",
        "mail_smtpauthtype": "PLAIN",
        "mail_smtpauth": 1,
        "mail_smtpname": "***REMOVED SENSITIVE VALUE***",
        "mail_smtppassword": "***REMOVED SENSITIVE VALUE***",
        "mail_from_address": "***REMOVED SENSITIVE VALUE***",
        "app_install_overwrite": [
            "admin_resource_booking_database",
            "occweb",
            "whiteboard",
            "fulltextsearch",
            "extract"
        ],
        "default_phone_region": "***REMOVED SENSITIVE VALUE***",
        "profile.enabled": false
    }
}

List of activated Apps

Enabled:
  - activity: 2.18.0
  - admin_resource_booking_database: 0.0.1
  - appointments: 1.15.2
  - bookmarks: 13.0.1
  - breezedark: 26.0.0
  - bruteforcesettings: 2.6.0
  - calendar: 4.4.4
  - circles: 26.0.0
  - cloud_federation_api: 1.9.0
  - comments: 1.16.0
  - contacts: 5.3.2
  - contactsinteraction: 1.7.0
  - dashboard: 7.6.0
  - dav: 1.25.0
  - deck: 1.9.2
  - drawio: 2.1.2
  - extract: 1.3.6
  - federatedfilesharing: 1.16.0
  - federation: 1.16.0
  - files: 1.21.1
  - files_fulltextsearch: 26.0.1
  - files_fulltextsearch_tesseract: 27.0.0
  - files_mindmap: 0.0.28
  - files_pdfviewer: 2.7.0
  - files_rightclick: 1.5.0
  - files_sharing: 1.18.0
  - files_trashbin: 1.16.0
  - files_versions: 1.19.1
  - firstrunwizard: 2.15.0
  - forms: 3.3.1
  - fulltextsearch: 26.0.1
  - fulltextsearch_elasticsearch: 26.0.2
  - groupfolders: 14.0.4
  - holiday_calendars: 0.3.0
  - logreader: 2.11.0
  - lookup_server_connector: 1.14.0
  - nextcloud_announcements: 1.15.0
  - notes: 4.8.1
  - notifications: 2.14.0
  - oauth2: 1.14.1
  - onlyoffice: 7.9.0
  - password_policy: 1.16.0
  - photos: 2.2.0
  - polls: 5.2.0
  - privacy: 1.10.0
  - provisioning_api: 1.16.0
  - recommendations: 1.5.0
  - related_resources: 1.1.0
  - serverinfo: 1.16.0
  - settings: 1.8.0
  - sharebymail: 1.16.0
  - side_menu: 3.10.3
  - spreed: 16.0.5
  - support: 1.9.0
  - survey_client: 1.14.0
  - suspicious_login: 4.4.0
  - systemtags: 1.16.0
  - tasks: 0.15.0
  - text: 3.7.2
  - theming: 2.1.1
  - twofactor_backupcodes: 1.15.0
  - twofactor_totp: 8.0.0
  - updatenotification: 1.16.0
  - user_oidc: 1.3.3
  - viewer: 1.10.0
  - weather_status: 1.6.0
  - workflowengine: 2.8.0
Disabled:
  - admin_audit: 1.16.0
  - encryption: 2.14.0
  - files_external: 1.18.0
  - user_ldap: 1.16.0
  - user_status: 1.6.0 (installed 1.4.0)

Nextcloud Signing status

No errors have been found.

Nextcloud Logs

No response

Additional info

used user backend: OIDC connect user backend for Nextcloud

Start by tracing the user-search path used for file sharing, event invitations, and polls, then inspect how disabled users are returned. Reproduce the search with a disabled account and add coverage for the expected result: only active users are suggested.