---
id: CVE-2026-85511
title: A flaw was found in EAP's Elytron
summary: >-
  A flaw was found in EAP's Elytron. An EAP application whose security domain is
  backed by an Elytron token-realm with oauth2-introspection would allow
  parameter substitution due to missing URL encoding.
severity: medium
cvss: 4.2
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N'
cwe:
  - CWE-290
vendor: Red Hat
product: eap8-activemq-artemis
affected:
  - eap8-activemq-artemis (all versions)
  - eap8-apache-cxf (all versions)
  - eap8-artemis-wildfly-integration (all versions)
  - eap8-bouncycastle (all versions)
  - eap8-cryptacular (all versions)
  - eap8-eap-product-conf-parent (all versions)
  - eap8-hibernate (all versions)
  - eap8-httpcomponents-asyncclient (all versions)
  - eap8-ironjacamar (all versions)
  - eap8-jackson-annotations (all versions)
  - eap8-jackson-core (all versions)
  - eap8-jackson-databind (all versions)
  - eap8-jackson-dataformats-text (all versions)
  - eap8-jackson-jaxrs-providers (all versions)
  - eap8-jackson-modules-base (all versions)
  - eap8-jackson-modules-java8 (all versions)
  - eap8-jakarta-xml-bind-api (all versions)
  - eap8-jaxb (all versions)
  - eap8-jaxbintros (all versions)
  - eap8-jboss-logging (all versions)
  - eap8-jboss-remoting (all versions)
  - eap8-jbossws-api (all versions)
  - eap8-jbossws-common-tools (all versions)
  - eap8-jbossws-cxf (all versions)
  - eap8-jbossws-jaxws-undertow-httpspi (all versions)
  - eap8-jbossws-spi (all versions)
  - eap8-jsf-impl (all versions)
  - eap8-log4j (all versions)
  - eap8-neethi (all versions)
  - eap8-netty (all versions)
  - eap8-netty-transport-native-epoll (all versions)
  - eap8-nimbus-jose-jwt (all versions)
  - eap8-parsson (all versions)
  - eap8-saaj-impl (all versions)
  - eap8-slf4j (all versions)
  - eap8-undertow (all versions)
  - eap8-wildfly (all versions)
  - eap8-wildfly-elytron (all versions)
  - eap8-wildfly-javadocs (all versions)
  - eap8-ws-commons-XmlSchema (all versions)
  - eap8-xml-security (all versions)
  - eap8-activemq-artemis (all versions)
  - eap8-apache-cxf (all versions)
  - eap8-artemis-wildfly-integration (all versions)
  - eap8-bouncycastle (all versions)
  - eap8-cryptacular (all versions)
  - eap8-eap-product-conf-parent (all versions)
  - eap8-hibernate (all versions)
  - eap8-httpcomponents-asyncclient (all versions)
  - eap8-ironjacamar (all versions)
published: '2026-09-18'
updated: '2026-09-25'
sourceUpdated: '2026-09-25T21:17:23.933'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-85511'
references:
  - url: 'https://access.redhat.com/errata/RHSA-2026:70228'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2026:70229'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2026:70230'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2026:70277'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/security/cve/CVE-2026-85511'
    label: secalert@redhat.com
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2483140'
    label: secalert@redhat.com
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-85511.json
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-85511'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-85511'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-18T16:43:50.598569Z'
epss: 0.0028
epssPercentile: 0.20343
ingestedAt: '2026-09-18T14:43:13.066Z'
patched:
  - jboss_eap_8_1_for_rhel 10
  - jboss_eap_8_1_for_rhel 8
  - jboss_eap_8_1_for_rhel 9
---

## Overview

A flaw was found in EAP's Elytron. An EAP application whose security domain is backed by an Elytron token-realm with oauth2-introspection would allow parameter substitution due to missing URL encoding.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Vendor advisories

- **RHSA-2026:70230** · Red Hat · fixed in: Red Hat JBoss EAP 8.1 for RHEL 10 · released 2026-09-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:70230)
- **RHSA-2026:70228** · Red Hat · fixed in: Red Hat JBoss EAP 8.1 for RHEL 8 · released 2026-09-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:70228)
- **RHSA-2026:70229** · Red Hat · fixed in: Red Hat JBoss EAP 8.1 for RHEL 9 · released 2026-09-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:70229)
- **Red Hat VEX** · Low · affected: Red Hat Data Grid 8, Red Hat Fuse 7, Red Hat Single Sign-On 7 · no fix planned: Red Hat Data Grid 8, Red Hat Fuse 7, Red Hat Single Sign-On 7 · updated 2026-09-25 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-85511.json)