I would say... There are no existing connectors but I think you can write your own and try to integrate both systems. More information you can get from this doc:
https://community.atlassian.com/t5/Crowd-articles/The-Crowd-team-is-looking-for-feedback-on-Server-amp-Data-Center/ba-p/738688 mentions that the Crowd team have Crowd as a SAML provider on the roadmap. While I haven't seen anything in the changelog about where this is up to, but connecting ServiceNow (which talks SAML) to Crowd will be straightforward.
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