Bug 2560217 (CVE-2026-115886)

Summary: CVE-2026-115886 mlflow: mlflow: Server-Side Request Forgery via insecure scorer deserialization
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: ilpinto, ltomasbo, ykashtan
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in MLflow. An unauthenticated remote attacker can conduct Server-Side Request Forgery (SSRF), where the application is tricked into making unauthorized network requests to arbitrary internal or external systems. By submitting crafted serialized scorer data to affected endpoints, an attacker can exploit insufficient validation during object deserialization to force the server to initiate outbound requests with attacker-controlled destinations and payloads. This issue can lead to unauthorized access to restricted internal resources or information disclosure.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-10-23 21:31:39 UTC 
MLflow is an open source AI engineering platform for agents, large language models, and machine learning models. From 3.12.0rc0 until 3.17.0, the scorer invoke, register, and GenAI evaluate endpoints, including unauthenticated POST /ajax-api/3.0/mlflow/scorer/invoke, accept serialized third-party scorer data that Scorer.model_validate_json resolves using a module-path allowlist without constraining the selected class or its constructor arguments. When optional trulens and trulens-providers-litellm packages are installed, an attacker can select mlflow.genai.scorers.trulens, choose a model URI outside MLflow's native provider registry so execution uses the LiteLLM fallback, and supply api_base and api_key values that cause the server to send an outbound request to an attacker-chosen or internal host with attacker-controlled headers and body. The vulnerable deserialization occurs before a tracking-store lookup or job submission. This issue is fixed in version 3.17.0.