CVE-2026-76166
mediumA flaw was found in mod_cluster's AdvertiseListenerImpl (org.jboss.modcluster core module).
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
Not reported by the source (unknown — not "none").
Weakness classification (CWE)
Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.
Mitigation & advisories
No vendor advisory or patch reference tagged by NVD. Check the references below.
References
- https://access.redhat.com/errata/RHSA-2026:93618 secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:93622 secalert@redhat.com
- https://access.redhat.com/security/cve/CVE-2026-76166 secalert@redhat.com
- https://bugzilla.redhat.com/show_bug.cgi?id=2510883 secalert@redhat.com