Bug 2492229 (CVE-2026-56121)

Summary: CVE-2026-56121 feast: Feast: Remote Code Execution via Unsafe Deserialization in gRPC Registry Server
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedCC: jkoehler, lphiri
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in Feast. This vulnerability allows unauthenticated or unauthorized attackers to achieve remote code execution. By sending a specially crafted gRPC request to the registry server, attackers can exploit an unsafe deserialization process. This enables them to execute operating system commands as the Feast service account, leading to a complete compromise of the affected system.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-06-24 16:01:20 UTC 
Feast before 0.63.0 contains an unsafe deserialization vulnerability that allows unauthenticated or unauthorized attackers to achieve remote code execution by sending a crafted gRPC request to the registry server. The user_defined_function.body field of an OnDemandFeatureView spec is decoded from base64 and passed to dill.loads() before any authorization check is performed, enabling attackers to embed a malicious serialized Python object with an arbitrary __reduce__ method to execute OS commands as the feast service account.