Files scan fails on filenames with invalid UTF-8 characters

⚠️ 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

Been running a few occ files:scan --all after moving a bunch of files, moved files and folders in stages, previously it worked, now when i moved the last folders with files, i get this error thrown

Exception during scan: An exception occurred while executing a query: SQLSTATE[22007]: Invalid datetime format: 1366 Incorrect string value: '\xF1o cor...' for column `squid`.`oc_filecache`.`name` at row 1
#0 /app/www/public/lib/private/DB/ConnectionAdapter.php(69): OC\DB\Exceptions\DbalException::wrap()
#1 /app/www/public/lib/private/DB/QueryBuilder/QueryBuilder.php(285): OC\DB\ConnectionAdapter->executeStatement()
#2 /app/www/public/lib/private/Files/Cache/Cache.php(305): OC\DB\QueryBuilder\QueryBuilder->executeStatement()
#3 /app/www/public/lib/private/Files/Cache/Scanner.php(276): OC\Files\Cache\Cache->insert()
#4 /app/www/public/lib/private/Files/Cache/Scanner.php(227): OC\Files\Cache\Scanner->addToCache()
#5 /app/www/public/lib/private/Files/Cache/Scanner.php(489): OC\Files\Cache\Scanner->scanFile()
#6 /app/www/public/lib/private/Files/Cache/Scanner.php(413): OC\Files\Cache\Scanner->handleChildren()
#7 /app/www/public/lib/private/Files/Cache/Scanner.php(418): OC\Files\Cache\Scanner->scanChildren()
#8 /app/www/public/lib/private/Files/Cache/Scanner.php(418): OC\Files\Cache\Scanner->scanChildren()
#9 /app/www/public/lib/private/Files/Cache/Scanner.php(418): OC\Files\Cache\Scanner->scanChildren()
#10 /app/www/public/lib/private/Files/Cache/Scanner.php(322): OC\Files\Cache\Scanner->scanChildren()
#11 /app/www/public/lib/private/Files/Utils/Scanner.php(246): OC\Files\Cache\Scanner->scan()
#12 /config/www/nextcloud/apps/files/lib/Command/Scan.php(165): OC\Files\Utils\Scanner->scan()
#13 /config/www/nextcloud/apps/files/lib/Command/Scan.php(255): OCA\Files\Command\Scan->scanFiles()
#14 /app/www/public/3rdparty/symfony/console/Command/Command.php(326): OCA\Files\Command\Scan->execute()
#15 /app/www/public/core/Command/Base.php(220): Symfony\Component\Console\Command\Command->run()
#16 /app/www/public/3rdparty/symfony/console/Application.php(1078): OC\Core\Command\Base->run()
#17 /app/www/public/3rdparty/symfony/console/Application.php(324): Symfony\Component\Console\Application->doRunCommand()
#18 /app/www/public/3rdparty/symfony/console/Application.php(175): Symfony\Component\Console\Application->doRun()
#19 /app/www/public/lib/private/Console/Application.php(187): Symfony\Component\Console\Application->run()
#20 /app/www/public/console.php(92): OC\Console\Application->run()
#21 /app/www/public/occ(33): require_once('...')
#22 {main}

Docker compose

services:
  nextcloud:
    image: lscr.io/linuxserver/nextcloud:latest
    container_name: nextcloud
    environment:
      - PUID=1000
      - PGID=1000
      - TZ=Europe/Stockholm
    volumes:
      - /docker/nextcloud/config:/config
      - /data/nextcloud_data:/data
    ports:
      - 6443:443
    restart: unless-stopped

  redis:
    image: redis:alpine
    restart: always
    command: redis-server --requirepass <password>

Steps to reproduce

Expected behavior

no error

Nextcloud Server version

33

Operating system

Debian/Ubuntu

PHP engine version

PHP 8.4

Web server

Other

Database engine version

MySQL

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

None

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": {
        "datadirectory": "***REMOVED SENSITIVE VALUE***",
        "instanceid": "***REMOVED SENSITIVE VALUE***",
        "passwordsalt": "***REMOVED SENSITIVE VALUE***",
        "secret": "***REMOVED SENSITIVE VALUE***",
        "trusted_domains": [
            "filer.gubbe.org"
        ],
        "dbtype": "mysql",
        "version": "33.0.0.16",
        "overwrite.cli.url": "https:\/\/filer.gubbe.org",
        "dbname": "***REMOVED SENSITIVE VALUE***",
        "dbhost": "***REMOVED SENSITIVE VALUE***",
        "dbtableprefix": "oc_",
        "mysql.utf8mb4": true,
        "dbuser": "***REMOVED SENSITIVE VALUE***",
        "dbpassword": "***REMOVED SENSITIVE VALUE***",
        "installed": true,
        "trusted_proxies": "***REMOVED SENSITIVE VALUE***",
        "mail_smtppassword": "***REMOVED SENSITIVE VALUE***",
        "mail_smtpname": "***REMOVED SENSITIVE VALUE***",
        "mail_domain": "***REMOVED SENSITIVE VALUE***",
        "mail_from_address": "***REMOVED SENSITIVE VALUE***",
        "mail_smtpmode": "smtp",
        "mail_smtpsecure": "ssl",
        "mail_smtphost": "***REMOVED SENSITIVE VALUE***",
        "mail_smtpauth": true,
        "mail_smtpport": "465",
        "mail_sendmailmode": "smtp",
        "mail_smtpstreamoptions": {
            "ssl": {
                "allow_self_signed": false,
                "verify_peer": true,
                "verify_peer_name": true
            }
        },
        "maintenance": false,
        "memcache.local": "\\OC\\Memcache\\Redis",
        "filelocking.enabled": true,
        "memcache.locking": "\\OC\\Memcache\\Redis",
        "redis": {
            "host": "***REMOVED SENSITIVE VALUE***",
            "port": 6379,
            "timeout": 0,
            "password": "***REMOVED SENSITIVE VALUE***"
        },
        "maintenance_window_start": 1,
        "upgrade.disable-web": true
    }
}

List of activated Apps

Enabled:
  - activity: 6.0.0-dev.0
  - admin_audit: 1.23.0
  - bookmarks: 16.1.3
  - bruteforcesettings: 6.0.0-dev.0
  - calendar: 6.2.1
  - checksum: 2.0.3
  - circles: 33.0.0
  - cloud_federation_api: 1.17.0
  - comments: 1.23.0
  - contacts: 8.4.1
  - contactsinteraction: 1.14.1
  - dashboard: 7.13.0
  - dav: 1.36.0
  - federatedfilesharing: 1.23.0
  - federation: 1.23.0
  - files: 2.5.0
  - files_accesscontrol: 4.0.0
  - files_downloadlimit: 5.1.0-dev.0
  - files_pdfviewer: 6.0.0-dev.0
  - files_reminders: 1.6.0
  - files_sharing: 1.25.2
  - files_trashbin: 1.23.0
  - files_versions: 1.26.0
  - firstrunwizard: 6.0.0-dev.0
  - logreader: 6.0.0
  - lookup_server_connector: 1.21.0
  - mail: 5.7.3
  - nextcloud_announcements: 5.0.0
  - notes: 4.13.0
  - notifications: 6.0.0
  - oauth2: 1.21.0
  - password_policy: 5.0.0-dev.0
  - photos: 6.0.0-dev.0
  - privacy: 5.0.0-dev.0
  - profile: 1.2.0
  - provisioning_api: 1.23.0
  - related_resources: 4.0.0-dev.0
  - richdocuments: 10.1.0
  - serverinfo: 5.0.0-dev.0
  - settings: 1.16.0
  - sharebymail: 1.23.0
  - support: 5.0.0
  - survey_client: 5.0.0-dev.0
  - systemtags: 1.23.0
  - text: 7.0.0-dev.3
  - theming: 2.8.0
  - theming_customcss: 1.20.0
  - twofactor_backupcodes: 1.22.0
  - twofactor_totp: 15.0.0-dev.0
  - updatenotification: 1.23.0
  - user_status: 1.13.0
  - viewer: 6.0.0-dev.0
  - weather_status: 1.13.0
  - webhook_listeners: 1.5.0
  - workflowengine: 2.15.0
Disabled:
  - app_api: 33.0.0 (installed 33.0.0)
  - encryption: 2.21.0
  - files_antivirus: 6.2.0 (installed 6.2.0)
  - files_external: 1.25.1
  - recommendations: 6.0.0-dev.0 (installed 6.0.0-dev.0)
  - spreed: 23.0.1 (installed 23.0.1)
  - suspicious_login: 11.0.0-dev.0
  - twofactor_nextcloud_notification: 7.0.0
  - user_ldap: 1.24.0

Nextcloud Signing status

No errors have been found.

Nextcloud Logs

{"reqId":"6FIbveaKBEQzqwBvanRS","level":2,"time":"2026-03-18T19:07:42+00:00","remoteAddr":"","user":"--","app":"core","method":"","url":"--","scriptName":"/app/www/public/occ","message":"normalizing failed for \"files/<user_folder>/<filename that have ? in it>\"","userAgent":"--","version":"33.0.0.16","occ_command":["/app/www/public/occ","files:scan"],"data":{"app":"core"},"id":"69baf807e0471"}


Filenames also seems to have characters like this in it 'thefilename'$'\217''_08.avi.jpg'

Additional info

No response

Start with lib/private/Files/Cache/Scanner.php and lib/private/Files/Cache/Cache.php, following the files:scan entry point in apps/files/lib/Command/Scan.php. Reproduce the failure with filenames containing invalid UTF-8 or the characters noted in the logs, then trace the normalization and database insert path. Done means occ files:scan completes without failing and affected filenames are handled consistently.