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CVE-2026-76166

Modcluster-core: mod_cluster advertise listener: unauthenticated dos via crafted multicast datagram PUBLISHED

Description (CNA)

A flaw was found in mod_cluster's AdvertiseListenerImpl (org.jboss.modcluster core module). A single crafted UDP multicast datagram with a valid HTTP status line and a "Server:" header but without the "Date:", "Digest:", and "Sequence:" headers triggers a NullPointerException in verifyDigest() that is not caught by the worker thread's exception handler. This causes the advertise listener thread to terminate permanently. The failure is silent (isListening() continues to return true) and persists until the node is restarted. The crash occurs before the AdvertiseSecurityKey comparison, so deployments with a configured security key are still affected.

Affected (CNA)

Vendor / productVersions
Red Hat / Red Hat JBoss Enterprise Application Platform 7affected
Red Hat / Red Hat JBoss Enterprise Application Platform 8affected
Red Hat / Red Hat JBoss Enterprise Application Platform Expansion Packaffected
Red Hat / Red Hat JBoss Web Server 5unknown
Red Hat / Red Hat JBoss Web Server 6affected
Red Hat / Red Hat JBoss Web Server 7affected
Red Hat / Red Hat Single Sign-On 7affected

CWE

CWE-476

References

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.