Copyright © 2012 Red Hat, Inc. All rights reserved. Important 2026-09-04T09:40:18 fastify: fastify: Unauthorized state changes and data disclosure via request body replacement 8.1 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N CWE-179

fastify versions before 5.12.2 treat the object resolved by a successful Ajv async validator as the value result protocol used by custom validator compilers. If a request that passes its route schema contains a property named value at the root, fastify replaces the entire request body with that property's value before the handler runs, so the handler receives a different object than the one that satisfied the schema. An authenticated low-privilege caller can use this to make nested data replace the validated body and trigger an operation the route schema did not authorize, leading to unauthorized state changes and data disclosure. Users should upgrade to fastify 5.12.2 or later.

A flaw was found in fastify. An authenticated low-privilege caller can exploit a vulnerability where the framework incorrectly processes the result of an Ajv asynchronous (async) validator. If a request body contains a root-level property named 'value', fastify replaces the entire request body with this property's content, bypassing the intended schema validation. This can lead to unauthorized state changes and the disclosure of sensitive data, as the application handler receives an unvalidated object.

This Important flaw in fastify allows an authenticated low-privilege user to bypass schema validation. By injecting a 'value' property into the request body, an attacker can trigger unauthorized state changes and data disclosure, impacting the integrity and confidentiality of data in affected Red Hat OpenShift AI and Red Hat OpenShift Dev Spaces deployments. Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability. Red Hat Enterprise Linux AI (RHEL AI) 3 Affected rhelai3/bootc-cuda-rhel9 Red Hat Enterprise Linux AI (RHEL AI) 3 Affected rhelai3/bootc-gaudi-rhel9 Red Hat Enterprise Linux AI (RHEL AI) 3 Affected rhelai3/bootc-rocm-rhel9 Red Hat Enterprise Linux AI (RHEL AI) 3 Affected rhelai3/disk-image-cuda-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-core-bff-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-dashboard-operator-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-dashboard-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-mod-arch-agent-ops-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-mod-arch-automl-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-mod-arch-autorag-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-mod-arch-eval-hub-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-mod-arch-gen-ai-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-mod-arch-maas-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-mod-arch-mlflow-rhel9 Red Hat OpenShift AI (RHOAI) Affected rhoai/odh-mod-arch-model-registry-rhel9 Red Hat OpenShift Dev Spaces Affected devspaces/dashboard-rhel9 https://www.cve.org/CVERecord?id=CVE-2026-84504 https://nvd.nist.gov/vuln/detail/CVE-2026-84504 https://cna.openjsf.org/security-advisories.html https://github.com/fastify/fastify/security/advisories/GHSA-667r-xxjv-c9mm