CVE-2026-56121

Exploitation

Public exploit code exists. CISA's assessment records a public proof of concept. That is not a report of exploitation in the wild.

SSVC decision

• ExploitationpocPublic proof-of-concept exploit code exists. Not a report of exploitation in the wild.
• AutomatableyesAn attacker can reliably automate reconnaissance through exploitation, so this scales.
• Technical ImpacttotalSuccessful exploitation gives total control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

1.40% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 72.3% of scored records. A rank, not a probability.

NVD base score

9.3 (CVSS v4.0), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

NVD analysis status

Deferred. NVD last modified this record on 2026-10-25.

Red Hat severity

Important. Red Hat's rating for its own products, not a CVSS rating.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2026-06-24 14:49Z4 MO AGO

Last updated

2026-08-28 12:04Z2 MO AGO

Reserved

2026-06-18

Assigning CNA

VulnCheck

Record state

PUBLISHED

Severity

Critical (CVSS 9.3)

CNA CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Weaknesses

• CWE-502Deserialization of Untrusted DataBase

Data version

5.2

Document digest

6526cc8261d9f0c699315b95cac9a13008c82fb414aee687d4df2a2422ebe70c

• huntr.comHuntr Disclosurehttps://huntr.com/bounties/d64b8111-180b-46ba-afa3-c877fda2ede6technical-descriptionexploit
• github.comRelease Noteshttps://github.com/feast-dev/feast/releases/tag/v0.63.0release-notes
• github.comPatch Commithttps://github.com/feast-dev/feast/commit/835cda8e2c1359f1f496ad72701dbd6a73bdb25apatch
• www.vulncheck.comhttps://www.vulncheck.com/advisories/feast-unauthenticated-rce-via-applyfeatureview-grpc-deserializationthird-party-advisory
• access.redhat.comhttps://access.redhat.com/security/cve/CVE-2026-56121vdb-entryx_refsource_REDHAT
• bugzilla.redhat.comRHBZ#2492229https://bugzilla.redhat.com/show_bug.cgi?id=2492229issue-trackingx_refsource_REDHAT
• security.access.redhat.comhttps://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-56121.jsonx_sadp-csaf-vex
• access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:60520vendor-advisoryx_refsource_REDHAT