GitHub Advisoryadvisory · PyPI
GHSA-q63x-9pfm-mjx4 Feast vulnerable to unsafe deserialization RCE in registry server via UDF proto
CRITICAL
Official page ↗
- Aliases
- CVE-2026-56121
- Ecosystem
- PyPI
- Packages
- feast
- Severity
- Critical
- CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Weaknesses
- CWE-502
- Reviewed
- 2026-11-03
Affected packages
• PyPI feast: < 0.63.0 → fixed in 0.63.0
Description
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.
Related
Alias · CVE (1)
- CVE-2026-56121 Feast before 0.63.0 contains an unsafe deserialization vulnerability that allows unauthenticated or unauthorized attackers to achieve… vulnerability
Weakness · CWE (1)
- CWE-502 Deserialization of Untrusted Data weakness
References
- https://nvd.nist.gov/vuln/detail/CVE-2026-56121 advisory
- https://github.com/feast-dev/feast/commit/835cda8e2c1359f1f496ad72701dbd6a73bdb25a web
- https://access.redhat.com/errata/RHSA-2026:60520 web
- https://access.redhat.com/security/cve/CVE-2026-56121 web
- https://bugzilla.redhat.com/show_bug.cgi?id=2492229 web
- https://github.com/feast-dev/feast package
- https://github.com/feast-dev/feast/releases/tag/v0.63.0 web
- https://huntr.com/bounties/d64b8111-180b-46ba-afa3-c877fda2ede6 web
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-56121.json web
- https://www.vulncheck.com/advisories/feast-unauthenticated-rce-via-applyfeatureview-grpc-deserialization web