CVE-2026-67426 in flyto-core
Summary
by MITRE • 07/29/2026
Flyto2 Core is an execution kernel for automation and AI-agent workflows. Prior to 2.26.7, the standalone flyto-verification service in src/core/verification_service.py exposes unauthenticated POST /run on 0.0.0.0:8344 and uses client-supplied callback_url for an outbound POST with X-Internal-Key: $FLYTO_RUNNER_SECRET while bypassing target_allowed, allowing unauthenticated SSRF and runner secret exfiltration. This issue is fixed in version 2.26.7.
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Analysis
by VulDB Data Team • 07/29/2026
The Flyto2 Core platform represents a sophisticated execution kernel designed for automation and AI-agent workflows, serving as a critical component in modern enterprise automation environments. The vulnerability analysis reveals a significant security flaw within the standalone verification service that has persisted across multiple versions prior to 2.26.7. This particular service operates on the network interface 0.0.0.0:8344, making it accessible from any network interface and presenting an attack surface that lacks proper authentication mechanisms.
The technical implementation flaw resides in the verification_service.py file where the POST endpoint /run accepts client-supplied callback_url parameters without adequate validation or authentication checks. This design pattern creates a dangerous scenario where external actors can directly invoke the service endpoint and manipulate the callback URL parameter to redirect requests to arbitrary destinations. The vulnerability manifests through an insecure direct object reference (CWE-639) combined with server-side request forgery (CWE-918), allowing attackers to bypass intended access controls that should normally validate target_allowed parameters.
The operational impact of this vulnerability extends beyond simple unauthorized access, as it enables full secret exfiltration through the use of X-Internal-Key header containing the $FLYTO_RUNNER_SECRET value. This represents a critical information disclosure issue where internal system secrets can be extracted by any unauthenticated attacker who can reach the affected service endpoint. The attack vector follows the pattern described in the ATT&CK framework under T1566.002 (Prephishing) and T1071.004 (Application Layer Protocol: DNS) where attackers exploit insecure service endpoints to gain unauthorized access to sensitive internal infrastructure components.
The flaw demonstrates a classic case of insufficient input validation combined with improper access control mechanisms, allowing malicious actors to construct crafted requests that bypass the intended security boundaries. The service's failure to properly validate the callback_url parameter against allowed targets creates an open redirect vulnerability that can be exploited for various attack scenarios including internal network reconnaissance and further privilege escalation attempts. Organizations utilizing Flyto2 Core versions prior to 2.26.7 face significant risk of credential compromise and potential system takeover through this vulnerability.
Security mitigations for this vulnerability require immediate implementation of proper authentication mechanisms on the verification service endpoints, along with strict validation of all client-supplied URLs against a predefined whitelist of allowed domains or IP addresses. The fix implemented in version 2.26.7 addresses these concerns by introducing proper access controls and input sanitization that prevents unauthenticated exploitation while maintaining the service's intended functionality. Organizations should also consider implementing network segmentation to limit exposure of internal verification services and deploy monitoring solutions to detect unusual patterns of requests to these endpoints. The vulnerability serves as a reminder of the critical importance of validating all external inputs and implementing defense-in-depth strategies to protect against server-side request forgery attacks that can lead to complete system compromise.