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.
What this means for your business
- An attacker can use it remotely, over a network, without a login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 0.9% chance of attack attempts being seen in the next 30 days, ranking above 59% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
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Scoring
- CVSS
- 8.1 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H- Weakness
- CWE-184
- Assigned by
- secalert@redhat.com
Dates
- Published
- 2026-09-01
- Last modified
- 2026-09-02
- Sources
- NVD