CVE-2026-76166

medium

Published 2026-08-19 · Modified 2026-08-19

Discuss on Community Propose mitigation

CVSS v3

4.3

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

CVSS v4 NEW

—

not yet in upstream

VIR risk

4.3

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.

Predictions

Exploit likelihood

43%

Patch ETA

—

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.

Propose a mitigation on Community Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

References

CWEs

CWE-476

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.