Category Archives: Oracle Database

Oracle 12c EPG (XDB) uses digest authentication in stead of basic.

After an upgrade from 11g to 12c, an application using the external procedural gateway (EPG) and basic authentication got a 401: not authorized.

It appears that in 12c, the EPG uses digest authentication in stead of basic authentication by default. You won’t notice this using a browser or WGET, but applications using CURL will fail.

Digest is a two-step way of authenticating, returning a so called nonce first to be used to encrypt the username and password in the request.

Using CURL, this can be solved by adding – -digest before the request.

An other option is to reset EPG (actually XDB) to use basic again by editing xdbconfig.xml (a row in the table XDB$CONFIG).

This can be done using this call:

call dbms_xdb.cfg_update(updateXML(
, ‘/xdbconfig/sysconfig/protocolconfig/httpconfig/authentication/allow-mechanism/text()’
, ‘basic’))

followed by


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