Vulnerability-Lookup

GHSA-P4RG-FFFF-6PMM

Vulnerability from github – Published: 2026-08-19 12:32 – Updated: 2026-08-19 12:32

Details

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.

Severity

4.3 (Medium)


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

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{
  "affected": [],
  "aliases": [
    "CVE-2026-76166"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-476"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-19T10:16:38Z",
    "severity": "MODERATE"
  },
  "details": "A flaw was found in mod_cluster\u0027s 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\u0027s 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.",
  "id": "GHSA-p4rg-ffff-6pmm",
  "modified": "2026-08-19T12:32:22Z",
  "published": "2026-08-19T12:32:22Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-76166"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/security/cve/CVE-2026-76166"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2510883"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-76166 (GCVE-0-2026-76166)

Vulnerability from cvelistv5 – Published: 2026-08-19 10:01 – Updated: 2026-08-19 10:01

Title

Modcluster-core: mod_cluster advertise listener: unauthenticated dos via crafted multicast datagram

Summary

Severity

4.3 (Medium)


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

CWE

CWE-476 - NULL Pointer Dereference

Assigner

redhat redhat root

References

2 references

URL	Tags
https://access.redhat.com/security/cve/CVE-2026-76166	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2510883	issue-trackingx_refsource_REDHAT

Impacted products

7 products

Vendor	Product	Version
Red Hat	Red Hat JBoss Enterprise Application Platform 7	cpe:/a:redhat:jboss_enterprise_application_platform:7
Red Hat	Red Hat JBoss Enterprise Application Platform 8	cpe:/a:redhat:jboss_enterprise_application_platform:8
Red Hat	Red Hat JBoss Enterprise Application Platform Expansion Pack	cpe:/a:redhat:jbosseapxp
Red Hat	Red Hat JBoss Web Server 5	cpe:/a:redhat:jboss_enterprise_web_server:5
Red Hat	Red Hat JBoss Web Server 6	cpe:/a:redhat:jboss_enterprise_web_server:6
Red Hat	Red Hat JBoss Web Server 7	cpe:/a:redhat:jboss_enterprise_web_server:7
Red Hat	Red Hat Single Sign-On 7	cpe:/a:redhat:red_hat_single_sign_on:7

Date Public

2026-08-04 00:00

Credits

Red Hat would like to thank Kien Pham (Ninh Thanh Cyber Security (NTCS)) and Ta Duc Thien (Ninh Thanh Cyber Security (NTCS)) for reporting this issue.

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JSON

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  "dataType": "CVE_RECORD",
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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

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GHSA-P4RG-FFFF-6PMM

CVE-2026-76166 (GCVE-0-2026-76166)

Tags

Sightings

Nomenclature