Decryption of files in external storage mounted via WebDAV does not work

Nextcloud version: 15.0.7
Operating system and version: CentOS 6
Apache or nginx version: don’t know (shared hosting)
PHP version: 7.2.19

The issue you are facing:

When mounting external storage via WebDAV, the data is encrypted, but the decryption does not work.

When I mount the external storage via SFTP decryption works fine.Dieser Text wird versteckt

Is this the first time you’ve seen this error?: Y

Steps to replicate it:

  1. Enable server-side encryption and allow users to mount external storage
  2. Mount external storage (in my case strato HiDrive) via WebDAV
  3. Add some files via Nextcloud web interface or local nextcloud client
  4. Try to open the files via nextcloud web interface.
  5. “Missing signature” error occurs

The output of your Nextcloud log in Admin > Logging:

The output of your config.php file in /path/to/nextcloud (make sure you remove any identifiable information!):

$CONFIG = array (
  'instanceid' => '',
  'passwordsalt' => '',
  'secret' => '',
  'trusted_domains' => 
  array (
    0 => '',
  'datadirectory' => '/home/[USER]/nextcloud_data',
  'overwrite.cli.url' => '',
  'overwritewebroot' => '/',
  'dbtype' => 'mysql',
  'version' => '',
  'dbname' => '',
  'dbhost' => 'localhost',
  'dbtableprefix' => 'oc_',
  'dbuser' => '',
  'dbpassword' => '',
  'installed' => true,
  'mail_from_address' => 'nextcloud',
  'mail_smtpmode' => 'sendmail',
  'mail_domain' => '',
  'loglevel' => 0,
  'theme' => '',
  'filelocking.enabled' => 'true',
  'memcache.locking' => '\\OC\\Memcache\\Redis',
  'memcache.local' => '\\OC\\Memcache\\Redis',
  'redis' => 
  array (
    'host' => '/home/[USER]/.redis/sock',
    'port' => 0,
    'timeout' => 0,
  'overwriteprotocol' => 'https',
  'trashbin_retention_obligation' => '0,0',
  'maintenance' => false,
  'mail_smtpauthtype' => 'LOGIN',
  '' => 'stable',
  'twofactor_enforced' => 'false',
  'twofactor_enforced_groups' => 
  array (
  'twofactor_enforced_excluded_groups' => 
  array (
  'skeletondirectory' => '',
  'htaccess.RewriteBase' => '/',

The output of your Apache/nginx/system log in /var/log/____:

don't have that

Anything went wrong during upload? Perhaps encryption did not finish or file was not fully transferred to external storage, or db timeout?
Problem is that without the signature it does not decrypt at all, it would be interesting to know if it is possible to read the file (then the transfer and encryption process went fine and it’s an issue with the signature). If you find server logfiles (perhaps at customer interface or some folder in your webspace), they could show such an error (if not ignored by configuration).

Perhaps an issue for the bug tracker …


thanks for your reply. I’ll ask my provider about the server logfiles. Maybe they can help.
What do you mean by bugtracker. How can I activate it?

Thanks again