CVE-2026-76166: medium-severity vulnerability in Red Hat JBoss Enterprise Application Platform 7
Modcluster-core: mod_cluster advertise listener: unauthenticated dos via crafted multicast datagram
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13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 4.3epss 2.7%
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.
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Affected products
Red Hat · Red Hat JBoss Enterprise Application Platform 7Red Hat · Red Hat JBoss Enterprise Application Platform 8Red Hat · Red Hat JBoss Enterprise Application Platform Expansion PackRed Hat · Red Hat JBoss Web Server 5Red Hat · Red Hat JBoss Web Server 6Red Hat · Red Hat JBoss Web Server 7.0.3Red Hat · Red Hat JBoss Web Server 7.0 on RHEL 10Red Hat · Red Hat JBoss Web Server 7.0 on RHEL 8Red Hat · Red Hat JBoss Web Server 7.0 on RHEL 9Red Hat · Red Hat Single Sign-On 7Related CVEs — Red Hat JBoss Enterprise Application Platform 7
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