CVE-2026-84218 (CVSS 8.1)

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.

Is your site exposed to CVE-2026-84218?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

8.1

HIGH

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS — Exploit Prediction

0.0095

Probability of exploitation

0.60%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-184 CWE-184

References

Other 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

Frequently Asked Questions

What is CVE-2026-84218? +

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. It has a CVSS v3.1 base score of 8.1 (HIGH).

How severe is CVE-2026-84218? +

CVE-2026-84218 has a CVSS v3.1 score of 8.1 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0095, placing it in the 1th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-84218? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2026-93598

ArcadeDB (Maven artifact com.arcadedb:arcadedb-engine) through 26.8.1 contains an incomplete deny-list in the polyglot script sandbox: com.arcadedb.query.polyglot.HostClassLookupFilter.DENIED lists java.util.ResourceBundle as a …

CVE-2026-54090

File Browser is a file managing interface for uploading, deleting, previewing, renaming, and editing files within a specified directory. Prior …

CVE-2026-126206

Loofah is a general library for manipulating and transforming HTML/XML documents and fragments, built on top of Nokogiri. In 2.25.2, …

CVE-2026-126209

Loofah is a general library for manipulating and transforming HTML/XML documents and fragments, built on top of Nokogiri. From 2.25.0 …

CVE-2026-126361

Astro is a web framework for content-driven websites. Prior to 7.4.5, Astro rendered a string used as a dynamic element …

CVE-2025-71355

Picklescan before 0.0.25 fails to detect unsafe global functions in the Numpy library, allowing attackers to bypass static analysis and …

CVE-2026-84218