VulnerabilityAwaiting Analysis

CVE-2026-76166

The crash occurs before the AdvertiseSecurityKey comparison, so deployments with a configured security key are still affected.

MEDIUM 4.3EPSS 0.84%

Does this matter?

Lower severity and a low EPSS score (0.84%). Track it; it rarely justifies an emergency change on its own.

Description

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: 4.3 MEDIUMCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
EPSS: 0.84% probability · 56th percentile
CISA KEV: Not listed
Weakness: CWE-476
Source: secalert@redhat.com

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.