Here you can find additional information related to security and privacy of Post Webhooks for Bitbucket.
End User License Agreement
Security Bug Bounty
Post Webhooks for Bitbucket is enrolled on the Bug Bounty program. More information can be found here https://www.atlassian.com/licensing/marketplace#general-faqs
Security Self Assessment Questionaire
Post Webhooks for Bitbucket is part of the Move Work Forward Atlassian Marketplace Partner app portfolio. Move Work Forward provides all required answers to Atlassian annually.
More details can be found here https://developer.atlassian.com/platform/marketplace/security-self-assessment-program/