REDHAT-BUG-2527210: Medium severity Ansible Ansible Automation Platform automation-controller vulnerability

A flaw was found in the Ansible Automation Platform automation-controller webhook receivers. The Bitbucket Data Center webhook receiver at POST /api/controller/v2/{jobtemplates,workflowjobtemplates}/<pk>/bitbucketdc/ is intentionally unauthenticated (permissionclasses=(AllowAny,), authenticationclasses=()) and authorizes requests by verifying an HMAC over the request body keyed by the per-template webhookkey. BitbucketDcWebhookReceiver.mustchecksignature() returns False when the X-Event-Key request header is 'diagnostics:ping', because Bitbucket does not sign ping requests. This carve-out is evaluated only after the receiver has already resolved the target template: getobject() filters templates to those with webhookservice='bitbucketdc' and a non-empty webhookkey and raises PermissionDenied (HTTP 403) when no template matches, whereas a matching template proceeds past the skipped signature check to the ping short-circuit and returns HTTP 200 with the body "Webhook ignored". As a result, an unauthenticated remote attacker who sends a diagnostics:ping request to each template ID observes a 200-vs-403 response discrepancy that reveals exactly which Job Template and Workflow Job Template IDs have Bitbucket DC webhooks configured, with no credentials and no knowledge of the webhookkey. This is unauthenticated reconnaissance: it confirms valid template IDs, reveals which automation is wired to Bitbucket Data Center, and lets an attacker focus subsequent webhookkey brute-force or SCM-side spoofing attempts on the small set of templates that would actually accept signed payloads. The ping path performs no action and no secret values are disclosed.

Upstream: https://github.com/ansible/tower (awx) Affected file: awx/api/views/webhooks.py:306-308 (BitbucketDcWebhookReceiver.mustchecksignature), with webhooks.py:69-78 (getobject) and :144-146 (post ping short-circuit)