CVE-2026-56121

CRITICAL

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.

CVSS v3.1 Score

9.8
CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Published: 6/24/2026Modified: 6/30/2026

Related Intelligence (1)

CRITICALVulnerability

NVD CRITICAL: CVE-2026-56121 — Feast before 0.63.0 contains an unsafe deserialization vulnerability that allows...

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 e

CVE-2026-56121
NIST NVD

References (7)

https://github.com/feast-dev/feast/commit/835cda8e2c1359f1f496ad72701dbd6a73bdb25ahttps://github.com/feast-dev/feast/releases/tag/v0.63.0https://huntr.com/bounties/d64b8111-180b-46ba-afa3-c877fda2ede6https://www.vulncheck.com/advisories/feast-unauthenticated-rce-via-applyfeatureview-grpc-deserializationhttps://access.redhat.com/security/cve/CVE-2026-56121https://bugzilla.redhat.com/show_bug.cgi?id=2492229https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-56121.json