CVE-2026-76166

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 v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/security/cve/CVE-2026-76166
https://bugzilla.redhat.com/show_bug.cgi?id=2510883

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-19 10:16

Updated : 2026-08-20 16:18

NVD link : CVE-2026-76166

Mitre link : CVE-2026-76166

CVE.ORG link : CVE-2026-76166

JSON object : View

Products Affected

No product.

CWE

CWE-476

NULL Pointer Dereference

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