CVE-2026-73840 in OpenChoreo
Summary
by MITRE • 08/14/2026
OpenChoreo is a complete, open-source developer platform for Kubernetes. Prior to 1.0.3, 1.1.3, and 1.2.0-rc.2, the POST /api/v1alpha1/autobuild endpoint in internal/openchoreo-api/api/handlers/webhook_handler.go selected a webhook provider from caller-controlled X-Event-Key, accepted Bitbucket requests without HMAC-SHA256 in X-Hub-Signature or a configured bitbucket-secret, and allowed unauthenticated build triggers for components matched by repository URL and branch, including cross-provider triggers using attacker-supplied commit SHAs. This issue is fixed in versions 1.0.3, 1.1.3, and 1.2.0-rc.2.
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Analysis
by VulDB Data Team • 08/14/2026
The OpenChoreo platform presents a critical authentication and authorization vulnerability in its webhook handling mechanism that affects multiple version ranges prior to the security patches released in versions 1.0.3, 1.1.3, and 1.2.0-rc.2. This vulnerability resides within the POST /api/v1alpha1/autobuild endpoint located in internal/openchoreo-api/api/handlers/webhook_handler.go, where the system fails to properly validate incoming webhook requests from various providers including Bitbucket. The flaw stems from the system's reliance on caller-controlled X-Event-Key headers to determine which webhook provider should process the request, creating an arbitrary provider selection mechanism that bypasses normal validation procedures.
The technical implementation of this vulnerability allows for complete bypass of authentication mechanisms through a combination of weak signature verification and lack of proper access control. Specifically, the system accepts Bitbucket webhook requests without requiring HMAC-SHA256 signatures in the X-Hub-Signature header or any configured bitbucket-secret, making it trivial for attackers to forge legitimate webhook notifications. This weakness is further compounded by the system's acceptance of unauthenticated build triggers that can be initiated based on repository URL and branch matching criteria, enabling attackers to trigger builds across arbitrary component configurations.
The operational impact of this vulnerability extends beyond simple authentication bypass to include potential code execution and system compromise through cross-provider triggering capabilities. Attackers can leverage the system's lack of proper validation to supply their own commit SHAs and trigger builds against components they don't own or control, potentially leading to unauthorized deployments, code injection attacks, or supply chain compromises. The vulnerability affects the core build automation functionality of OpenChoreo, making it possible for malicious actors to initiate automated workflows without proper authorization, which directly violates fundamental security principles of authentication and access control.
This vulnerability maps directly to CWE-345 Insufficient Verification of Data Authenticity and CWE-287 Improper Authentication, while also aligning with ATT&CK techniques including T1078 Valid Accounts for legitimate account use and T1203 Exploitation for Client Execution. The attack surface is particularly dangerous because it combines multiple weaknesses that allow attackers to not only bypass authentication but also manipulate the build process itself. The fix implemented in versions 1.0.3, 1.1.3, and 1.2.0-rc.2 addresses these issues by enforcing proper signature validation for Bitbucket requests, implementing required HMAC-SHA256 verification, and establishing proper authentication checks before allowing any build triggers to proceed. Organizations using OpenChoreo should immediately upgrade to these patched versions to prevent exploitation of this critical vulnerability that could lead to unauthorized code execution and system compromise within their Kubernetes environments.