CVE-2026-84218 — A flaw was found in Jolokia's JSR-160 proxy functionality where insufficient validation…¶
Key facts
CVE-2026-84218 is a High (8.1) vulnerability: A flaw was found in Jolokia's JSR-160 proxy functionality where insufficient validation…. This entry ships a detection-only PoC and a Docker test lab.
| CVE | CVE-2026-84218 |
| Severity | High (8.1) |
| Detection / prevention | — |
| PoC | poc.py |
| Source | 2026/CVE-2026-84218/ |
Details¶
English | 한국어
Description¶
A flaw was found in Jolokia's JSR-160 proxy functionality where insufficient validation of client-controlled JMX service URLs allows a bypass of the denylist introduced to mitigate CVE-2018-1000130. The proxy accepts a target.url value from a Jolokia POST request and passes it to JMXServiceURL and JMXConnectorFactory for establishing the remote JMX connection. The existing denylist only rejects URLs matching service:jmx:rmi:///jndi/ldap:.*, which can be bypassed using alternative valid JMX service URL forms, including ldaps:// schemes or LDAP URLs with a non-empty JMX host component. These URLs are accepted as valid JMXServiceURL objects and can cause the Jolokia agent JVM to perform a JNDI lookup against an attacker-controlled LDAP endpoint. This can result in server-side request forgery (SSRF), forwarding of supplied JMX credentials to the remote endpoint, and potentially remote code execution depending on the classes and configuration available in the target JVM.
Vulnerability Details¶
| Property | Value |
|---|---|
| CVE ID | CVE-2026-84218 |
| Type | SSRF |
| CVSS Score | 8.1 |
Proof of Concept¶
Download¶
# Download PoC script
curl -O https://raw.githubusercontent.com/fankh/vulnerability-poc/main/2026/CVE-2026-84218/poc.py
Usage¶
# Run PoC against target
python3 poc.py --target <TARGET_URL>
# With authentication
python3 poc.py --target <TARGET_URL> --username <USER> --password <PASS>
⚠️ Warning: This PoC is for authorized security testing only. It uses detection-only techniques and does not exploit or damage target systems.
Test Lab¶
This repository includes a Docker-based test environment with both vulnerable and patched applications.
Quick Start¶
# Clone and navigate to CVE directory
cd CVE-2026-84218
# Start both applications
docker-compose up -d
# Run tests
./run-tests.sh # Linux/Mac
./run-tests.ps1 # Windows PowerShell
Application Endpoints¶
| Application | URL | Status |
|---|---|---|
| Vulnerable App | http://localhost:8080 | Shows vulnerability |
| Patched App | http://localhost:8081 | Demonstrates fix |
Directory Structure¶
├── README.md # English documentation
├── README_KO.md # Korean documentation
├── poc.py # PoC detection script
├── docker-compose.yml # Container orchestration
├── run-tests.sh # Linux/Mac test runner
├── run-tests.ps1 # Windows test runner
├── vulnerable-app/ # Vulnerable version
│ ├── app.py
│ ├── Dockerfile
│ └── requirements.txt
└── patched-app/ # Fixed version
├── app.py
├── Dockerfile
└── requirements.txt
References¶
- https://access.redhat.com/security/cve/CVE-2026-84218
- https://bugzilla.redhat.com/show_bug.cgi?id=2526752
- https://github.com/jolokia/jolokia/issues/1049
Generated by PoC Generator on 2026-09-02T13:58:50.733344549
Frequently asked questions¶
What is CVE-2026-84218?¶
CVE-2026-84218 is a High (8.1) vulnerability: A flaw was found in Jolokia's JSR-160 proxy functionality where insufficient validation…. This entry ships a detection-only PoC and a Docker test lab.
How do I detect CVE-2026-84218?¶
Run the detection-only PoC included with this entry against your Docker test lab to confirm whether a target is affected; pair it with your own IDS logging.
How do I block or mitigate CVE-2026-84218?¶
Upgrade to a fixed version per the vendor advisory; the NVD record lists the affected versions. Use the included PoC to verify your remediation.
For authorized security testing and research only. See the full source and NVD record.