[Bug]: LDAP exception after update to 32.0.1

⚠️ 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

LDAP is broken after updateing from 31.0.9. I tried to update twice. Same error. On other NC instance with other NC version or with NC version 31 it works fine. No config changed.

Steps to reproduce

1. Update from 31.0.9 to 31.0.10
2. Update from 31.0.10 to 32.0.1
3. Error occurs in LDAP

Expected behavior

LDAP works as before

Nextcloud Server version

32

Operating system

Debian/Ubuntu

PHP engine version

PHP 8.3

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. 31 to 32)

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": {
        "instanceid": "***REMOVED SENSITIVE VALUE***",
        "passwordsalt": "***REMOVED SENSITIVE VALUE***",
        "secret": "***REMOVED SENSITIVE VALUE***",
        "trusted_domains": [
            "portal.domain.ch",
            "10.10.2.111",
            "pi.mattig.ch"
        ],
        "datadirectory": "***REMOVED SENSITIVE VALUE***",
        "overwrite.cli.url": "https:\/\/portal.domain.ch\/nextcloud",
        "dbtype": "mysql",
        "version": "32.0.1.2",
        "dbname": "***REMOVED SENSITIVE VALUE***",
        "dbhost": "***REMOVED SENSITIVE VALUE***",
        "dbport": "",
        "dbtableprefix": "oc_",
        "dbuser": "***REMOVED SENSITIVE VALUE***",
        "dbpassword": "***REMOVED SENSITIVE VALUE***",
        "logtimezone": "UTC",
        "installed": true,
        "mail_smtpmode": "smtp",
        "mail_from_address": "***REMOVED SENSITIVE VALUE***",
        "mail_domain": "***REMOVED SENSITIVE VALUE***",
        "mail_smtphost": "***REMOVED SENSITIVE VALUE***",
        "mail_smtpport": "25",
        "mail_smtpstreamoptions": {
            "ssl": {
                "allow_self_signed": true,
                "verify_peer": false,
                "verify_peer_name": false
            }
        },
        "appstore.experimental.enabled": false,
        "enable_previews": false,
        "preview_concurrency_all": 1,
        "preview_concurrency_new": 1,
        "enabledPreviewProviders": [
            "OC\\Preview\\BMP"
        ],
        "maintenance": false,
        "ldapIgnoreNamingRules": false,
        "ldapProviderFactory": "\\OCA\\User_LDAP\\LDAPProviderFactory",
        "filelocking.enabled": "true",
        "memcache.local": "\\OC\\Memcache\\APCu",
        "memcache.locking": "\\OC\\Memcache\\Redis",
        "redis": {
            "host": "***REMOVED SENSITIVE VALUE***",
            "port": 6379
        },
        "updater.release.channel": "stable",
        "theme": "",
        "log_type": "file",
        "logfile": "\/var\/log\/nextcloud\/nextcloud.log",
        "loglevel": "3",
        "logdateformat": "F d, Y H:i:s",
        "skeletondirectory": "",
        "mail_smtpauthtype": "PLAIN",
        "mysql.utf8mb4": true,
        "auth.webauthn.enabled": false,
        "mail_sendmailmode": "smtp",
        "default_phone_region": "CH",
        "maintenance_window_start": 1,
        "remember_login_cookie_lifetime": 1296000,
        "session_lifetime": 3600,
        "session_keepalive": false,
        "auto_logout": true,
        "trusted_proxies": "***REMOVED SENSITIVE VALUE***",
        "app_install_overwrite": []
    }
}

List of activated Apps

Enabled:
  - activity: 5.0.0-dev.0
  - admin_audit: 1.22.0
  - app_api: 32.0.0
  - cloud_federation_api: 1.16.0
  - comments: 1.22.0
  - contactsinteraction: 1.13.1
  - dav: 1.34.2
  - federatedfilesharing: 1.22.0
  - files: 2.4.0
  - files_antivirus: 6.1.0
  - files_downloadlimit: 5.0.0-dev.0
  - files_external: 1.24.0
  - files_reminders: 1.5.0
  - files_sharing: 1.24.0
  - files_trashbin: 1.22.0
  - files_versions: 1.25.0
  - logreader: 5.0.0-dev.0
  - lookup_server_connector: 1.20.0
  - notifications: 5.0.0-dev.0
  - notify_push: 1.2.0
  - oauth2: 1.20.0
  - password_policy: 4.0.0-dev.0
  - photos: 5.0.0-dev.1
  - privacy: 4.0.0-dev.0
  - profile: 1.1.0
  - provisioning_api: 1.22.0
  - related_resources: 3.0.0-dev.0
  - serverinfo: 4.0.0-dev.0
  - settings: 1.15.1
  - text: 6.0.1
  - theming: 2.7.0
  - twofactor_backupcodes: 1.21.0
  - updatenotification: 1.22.0
  - user_ldap: 1.23.0
  - viewer: 5.0.0-dev.0
  - webhook_listeners: 1.3.0
  - workflowengine: 2.14.0
Disabled:
  - bruteforcesettings: 5.0.0-dev.0 (installed 1.2.0)
  - circles: 32.0.0 (installed 25.0.0)
  - dashboard: 7.12.0 (installed 7.0.0)
  - encryption: 2.20.0
  - federation: 1.22.0 (installed 1.0.1)
  - files_pdfviewer: 5.0.0-dev.0 (installed 2.0.1)
  - files_rightclick: 0.15.1 (installed 1.6.0)
  - firstrunwizard: 5.0.0-dev.0 (installed 2.3.0)
  - nextcloud_announcements: 4.0.0-dev.0 (installed 1.3.0)
  - ransomware_protection: 1.14.0 (installed 1.14.0)
  - recommendations: 5.0.0-dev.0 (installed 1.1.0)
  - sharebymail: 1.22.0 (installed 1.4.0)
  - support: 4.0.0-dev.0 (installed 1.0.0)
  - survey_client: 4.0.0-dev.0 (installed 0.1.5)
  - suspicious_login: 10.0.0-dev.0
  - systemtags: 1.22.0 (installed 1.4.0)
  - twofactor_nextcloud_notification: 6.0.0-dev.0
  - twofactor_totp: 14.0.0 (installed 3.0.1)
  - user_status: 1.12.0 (installed 1.0.1)
  - weather_status: 1.12.0 (installed 1.0.0)

Nextcloud Signing status

No errors have been found.

Nextcloud Logs

ServerNotAvailableException
Lost connection to LDAP server.

Additional info

An exception occured while running the setup check: OC\ServerNotAvailableException: Lost connection to LDAP server. in /var/www/nextcloud/apps/user_ldap/lib/LDAP.php:367 
Stack trace: 
#0 /var/www/nextcloud/apps/user_ldap/lib/LDAP.php(405): OCA\User_LDAP\LDAP->processLDAPError() 
#1 /var/www/nextcloud/apps/user_ldap/lib/LDAP.php(287): OCA\User_LDAP\LDAP->postFunctionCall() 
#2 /var/www/nextcloud/apps/user_ldap/lib/LDAP.php(44): OCA\User_LDAP\LDAP->invokeLDAPMethod() 
#3 /var/www/nextcloud/apps/user_ldap/lib/Connection.php(752): OCA\User_LDAP\LDAP->bind() 
#4 /var/www/nextcloud/apps/user_ldap/lib/Connection.php(644): OCA\User_LDAP\Connection->bind() 
#5 /var/www/nextcloud/apps/user_ldap/lib/Connection.php(234): OCA\User_LDAP\Connection->establishConnection() 
#6 /var/www/nextcloud/apps/user_ldap/lib/Connection.php(242): OCA\User_LDAP\Connection->init() 
#7 /var/www/nextcloud/apps/user_ldap/lib/Connection.php(739): OCA\User_LDAP\Connection->getConnectionResource() 
#8 /var/www/nextcloud/apps/user_ldap/lib/SetupChecks/LdapConnection.php(47): OCA\User_LDAP\Connection->bind() 
#9 /var/www/nextcloud/lib/private/SetupCheck/SetupCheckManager.php(34): OCA\User_LDAP\SetupChecks\LdapConnection->run() 
#10 /var/www/nextcloud/apps/settings/lib/Controller/CheckSetupController.php(132): OC\SetupCheck\SetupCheckManager->runAll() 
#11 /var/www/nextcloud/lib/private/AppFramework/Http/Dispatcher.php(204): OCA\Settings\Controller\CheckSetupController->check() 
#12 /var/www/nextcloud/lib/private/AppFramework/Http/Dispatcher.php(118): OC\AppFramework\Http\Dispatcher->executeController() 
#13 /var/www/nextcloud/lib/private/AppFramework/App.php(153): OC\AppFramework\Http\Dispatcher->dispatch() 
#14 /var/www/nextcloud/lib/private/Route/Router.php(321): OC\AppFramework\App::main() 
#15 /var/www/nextcloud/lib/base.php(1061): OC\Route\Router->match() 
#16 /var/www/nextcloud/index.php(25): OC::handleRequest() 
#17 {main}

Start with apps/user_ldap/lib/LDAP.php and apps/user_ldap/lib/Connection.php, following the reported stack trace from SetupChecks/LdapConnection.php. Reproduce the upgrade path from 31.0.9 through 31.0.10 to 32.0.1 and inspect the LDAP setup-check failure. Done means the setup check completes and LDAP works without ServerNotAvailableException.