{"id":"CVE-2026-56121","title":"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","summary":"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_functi…","severity":"critical","cvss":9.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-502","CWE-502"],"published":"2026-06-24","updated":"2026-08-28","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-56121","references":[{"url":"https://github.com/feast-dev/feast/commit/835cda8e2c1359f1f496ad72701dbd6a73bdb25a","label":"disclosure@vulncheck.com"},{"url":"https://github.com/feast-dev/feast/releases/tag/v0.63.0","label":"disclosure@vulncheck.com"},{"url":"https://huntr.com/bounties/d64b8111-180b-46ba-afa3-c877fda2ede6","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/feast-unauthenticated-rce-via-applyfeatureview-grpc-deserialization","label":"disclosure@vulncheck.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:60520","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/security/cve/CVE-2026-56121","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2492229","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-56121.json","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}],"tags":["nvd","exploit-available"],"epss":0.01406,"epssPercentile":0.71424,"ingestedAt":"2026-08-29T00:27:53.736Z","exploits":{"github":3,"githubRepos":["https://github.com/0xdak/CVE-2026-56121_exploit","https://github.com/BiiTts/CVE-2026-56121-Feast-Unauth-RCE","https://github.com/joaovicdev/EXPLOIT-CVE-2026-56121"],"checkedAt":"2026-09-23T07:14:24.328Z"},"exploitAvailable":true,"slug":"CVE-2026-56121","body":"## Overview\n\nFeast 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.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"abyssal","depthScore":66,"depthScoreParts":{"impact":53.9,"likelihood":0.3,"exploitation":12,"ransomware":0},"changes":[{"seq":5358,"id":"CVE-2026-56121","ts":1788887271792,"field":"exploit_available","old":"false","new":"true"},{"seq":4241,"id":"CVE-2026-56121","ts":1788886386843,"field":"exploit_available","old":"true","new":"false"},{"seq":2997,"id":"CVE-2026-56121","ts":1788883050239,"field":"exploit_available","old":"false","new":"true"},{"seq":2026,"id":"CVE-2026-56121","ts":1788882454840,"field":"exploit_available","old":"true","new":"false"},{"seq":1100,"id":"CVE-2026-56121","ts":1788881891760,"field":"exploit_available","old":"false","new":"true"}]}