---
title: "CVE-2026-18948: Feast vulnerable to arbitrary code execution via unsafe deserialization of dill-serialized UDFs"
url: https://erroneo.us/security/cve/CVE-2026-18948/
description: "CVE-2026-18948 (feast (PyPI)): A flaw was found in Feast. The system improperly deserializes user-defined functions (UDFs) stored in its registry, which are…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-08-10
date_modified: 2026-11-03
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-18948"
kev: false
cvss: 9.9
epss: 0.01079
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-18948: Feast vulnerable to arbitrary code execution via unsafe deserialization of dill-serialized UDFs

**Signal:** Critical, preconditions apply. Severe if exploited, but exploitation needs conditions that may not apply to you. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 1.1% , percentile 65: FIRST’s model estimates a 1.1% chance of exploitation activity in the next 30 days, higher than 65% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
- Needs an account (low (any account)). Exposure depends on who can log in.
- Only applies if your dependency tree includes feast (PyPI) < 0.67.0, fixed in 0.67.0 . Check your lockfile, including transitive dependencies.

## What it is

A flaw was found in Feast. The system improperly deserializes user-defined functions (UDFs) stored in its registry, which are serialized using the 'dill' library. This allows a remote attacker to store a malicious UDF, leading to unauthenticated arbitrary code execution on the feature server in default configurations. An authenticated attacker can also achieve arbitrary code execution on the registry server by bypassing authorization checks during deserialization. This vulnerability can result in cross-tenant data access and lateral movement within the system.

## Affected packages

- PyPI `feast` < 0.67.0 → fixed: 0.67.0

## Affected products (CVE record)

- Red Hat Red Hat OpenShift AI 2.25: see advisory
- Red Hat Red Hat OpenShift AI 3.3: see advisory
- Red Hat Red Hat OpenShift AI 3.4: see advisory
- Red Hat Red Hat OpenShift AI 3.4: see advisory
- Red Hat Red Hat OpenShift AI (RHOAI): see advisory
- Red Hat Red Hat OpenShift AI (RHOAI): see advisory
- Red Hat Red Hat OpenShift AI (RHOAI): see advisory
- Red Hat Red Hat OpenShift AI (RHOAI): see advisory
- Red Hat Red Hat OpenShift AI (RHOAI): see advisory
- Red Hat Red Hat OpenShift AI (RHOAI): see advisory

## Severity

- redhat CVSS 3.1: 9.9 `CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H`
- GitHub CVSS 3.1: 9.9 `CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none , automatable no , technical impact total .
- FIRST EPSS (model of 2026-11-05): 1.08% probability of exploitation activity in the next 30 days; percentile 65.

## Sources

- [RHSA-2026:53261](https://access.redhat.com/errata/RHSA-2026:53261)
- [RHSA-2026:53262](https://access.redhat.com/errata/RHSA-2026:53262)
- [RHSA-2026:53263](https://access.redhat.com/errata/RHSA-2026:53263)
- [RHSA-2026:60520](https://access.redhat.com/errata/RHSA-2026:60520)
- [GitHub Advisory GHSA-gg2p-37pv-v7fq](https://github.com/advisories/GHSA-gg2p-37pv-v7fq)
- [CVE.org record CVE-2026-18948](https://www.cve.org/CVERecord?id=CVE-2026-18948)
- [NVD entry CVE-2026-18948](https://nvd.nist.gov/vuln/detail/CVE-2026-18948)
- [access.redhat.com](https://access.redhat.com/security/cve/CVE-2026-18948)
- [RHBZ#2511167](https://bugzilla.redhat.com/show_bug.cgi?id=2511167)
- [github.com](https://github.com/feast-dev/feast/issues/6827)
- [github.com](https://github.com/feast-dev/feast/pull/6861)
- [github.com](https://github.com/feast-dev/feast/commit/e0ef16ea1ed149ecd5dc9d4d0aa0fdbfa547f861)
- [github.com](https://github.com/feast-dev/feast/releases/tag/v0.67.0)

---
Source page: https://erroneo.us/security/cve/CVE-2026-18948/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt