[jboss-jira] [JBoss JIRA] (WFCORE-2615) Attribute allow-sasl-mechanisms is ignored in Elytron Authentication Configuration

[Ondrej Lukas (JIRA)]

    [ https://issues.jboss.org/browse/WFCORE-2615?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13390110#comment-13390110 ] 

Ondrej Lukas commented on WFCORE-2615:
--------------------------------------

[~dmlloyd] Thanks for response.

We see security risk here since attributes {{allow-sasl-mechanisms}} and {{allow-all-mechanisms}} can cause that user infers that all mechanisms are forbidden as default - based on principle of least privilege.

We have some questions based on your feedback:
* How is the "list of all known mechanisms" created? It is the list of mechanisms provided by server? Or it is hard coded somewhere in client?
* We understand that allowing some mechanisms which are not supported by configuration can be useful for standalone clients (e.g. CLI can ask user for password), but is there any scenario when it is useful for authentication-configuration in Elytron subsystem?
* Is there any way how to enforce usage of single concrete SASL mechanism?
* What should be an order of tried SASL mechanism? Is it defined somewhere or is it random? Should SASL mechanisms from {{allow-sasl-mechanisms}} have higher priority then other known mechanisms?

> Attribute allow-sasl-mechanisms is ignored in Elytron Authentication Configuration
> ----------------------------------------------------------------------------------
>
>                 Key: WFCORE-2615
>                 URL: https://issues.jboss.org/browse/WFCORE-2615
>             Project: WildFly Core
>          Issue Type: Bug
>          Components: Security
>    Affects Versions: 3.0.0.Beta10
>            Reporter: Ondrej Lukas
>            Assignee: Darran Lofthouse
>            Priority: Blocker
>         Attachments: dep.war, wireshark.pcapng
>
>
> In case when attribute allow-sasl-mechanisms from Elytron Authentication Configuration includes some SASL mechanisms then this attribute (and mechanisms configured there) is not taken into account during choosing SASL mechanism. It means that client tries to use all of mechanisms allowed on server side even if client does not allow them. e.g. in case when server side allowed DIGEST-MD5 and JBOSS-LOCAL-USER and client side allows PLAIN, then it tries to use DIGEST-MD5 and JBOSS-LOCAL-USER mechanisms.
> See log from wireshark in attachments. This is log for server configured through "Steps to Reproduce".
> This happens also for using allow-sasl-mechanisms from wildfly config and also for programatically configured client.
> We request blocker since it allows to use some SASL mechanisms even if they are not allowed on client side.



--
This message was sent by Atlassian JIRA
(v7.2.3#72005)