Answer in brief
CVE-2026-86404 records a High severity (CVSS 8.8) vulnerability in Artemis-server: artemis-jms-client: artemis-core-client: undertow-core: wildfly-messaging-activemq-subsystem: artemis messaging handlers in red hat eap permit deserialization by default. The current sources do not mark it as known exploited. The current feed maps Red Hat/artemis-core-client (generic), Red Hat/artemis-jms-client (generic), Red Hat/artemis-server (generic), Red Hat/undertow-core (generic) and additional mapped packages. Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 8.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Red Hat/artemis-core-client (generic), Red Hat/artemis-jms-client (generic), Red Hat/artemis-server (generic), Red Hat/undertow-core (generic) and additional mapped packages. Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Red Hat/artemis-core-clientgeneric | * | Not reported |
| Red Hat/artemis-jms-clientgeneric | * | Not reported |
| Red Hat/artemis-servergeneric | * | Not reported |
| Red Hat/undertow-coregeneric | * | Not reported |
| Red Hat/wildfly-messaging-activemq-subsystemgeneric | * | Not reported |
Published upstream
Sep 7, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 20, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Sep 7, 2026
EAP's Artemis deserialization configuration permits deserialization by default. ObjectMessage.getObject() uses ObjectInputStreamWithClassLoader, which implements allow-list/block-list filtering via its checkSecurity()/isTrustedType() method. However, by default both allow-list and block-list are empty. When the allow-list is empty (size == 0), isTrustedType() returns true for ALL classes. This means all classes are deserializable by default.
Quoted source text, attributed separately from HOL analysis.