CVE-2026-56121
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.
- Score
- CVSS 3.1 9.8 Critical
- Status
- Deferred - disclosure@vulncheck.com
- Published
- 2026-06-24
- Last modified
- 2026-10-25
- Weaknesses
- CWE-502
Affected products
References
- https://huntr.com/bounties/d64b8111-180b-46ba-afa3-c877fda2ede6
- https://github.com/feast-dev/feast/releases/tag/v0.63.0
- https://github.com/feast-dev/feast/commit/835cda8e2c1359f1f496ad72701dbd6a73bdb25a
- https://www.vulncheck.com/advisories/feast-unauthenticated-rce-via-applyfeatureview-grpc-deserialization
- https://access.redhat.com/security/cve/CVE-2026-56121
- https://bugzilla.redhat.com/show_bug.cgi?id=2492229
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-56121.json
- https://access.redhat.com/errata/RHSA-2026:60520
