Vulnerability-Lookup

(CVE-2026-19204)

Vulnerability from cleanstart – Published: 2026-09-20 00:37 – Updated: 2026-09-19 09:28 – Source website

Summary

client may send a WebSocket frame with an unknown opcode and a very large declared payload length, causing Jetty to attempt a large memory allocation and potentially exhaust the JVM heap

Details

Security vulnerability affects the apache-nifi package. A client may send a WebSocket frame with an unknown opcode and a very large declared payload length, causing Jetty to attempt a large memory allocation and potentially exhaust the JVM heap.

References

URL

Type

	https://github.com/cleanstart-dev/cleanstart-secu…	ADVISORY
	https://osv.dev/vulnerability/CVE-2026-19204	WEB
	https://nvd.nist.gov/vuln/detail/CVE-2026-19204	WEB

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "CleanStart",
        "name": "apache-nifi"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.10.0-r9"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "credits": [],
  "database_specific": {},
  "details": "Security vulnerability affects the apache-nifi package. A client may send a WebSocket frame with an unknown opcode and a very large declared payload length, causing Jetty to attempt a large memory allocation and potentially exhaust the JVM heap.",
  "id": "CLEANSTART-2026-SV46004",
  "modified": "2026-09-19T09:28:43Z",
  "published": "2026-09-20T00:37:25.040173Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/cleanstart-dev/cleanstart-security-advisories/tree/main/advisories/2026/CLEANSTART-2026-SV46004.json"
    },
    {
      "type": "WEB",
      "url": "https://osv.dev/vulnerability/CVE-2026-19204"
    },
    {
      "type": "WEB",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-19204"
    }
  ],
  "related": [],
  "schema_version": "1.7.3",
  "summary": "client may send a WebSocket frame with an unknown opcode and a very large declared payload length, causing Jetty to attempt a large memory allocation and potentially exhaust the JVM heap",
  "upstream": [
    "CVE-2026-19204"
  ]
}

CVE-2026-19204 (GCVE-0-2026-19204)

Vulnerability from cvelistv5 – Published: 2026-09-07 10:19 – Updated: 2026-09-08 15:06

Summary

A client may send a WebSocket frame with an unknown opcode and a very large declared payload length, causing Jetty to attempt a large memory allocation and potentially exhaust the JVM heap. This occurs when auto-fragmentation is enabled, as unknown opcodes bypass the normal maximum frame size handling and payload allocation occurs before the opcode is validated.

Severity

8.7 (High)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-08 15:06 UTC

CWE

CWE-770 - Allocation of resources without limits or throttling
CWE-789 - Memory allocation with excessive size value

Assigner

eclipse mitre root

References

1 reference

URL	Tags
https://github.com/jetty/jetty.project/security/a…

Impacted products

1 product

Vendor	Product	Version
Eclipse Foundation	Eclipse Jetty	Affected: 12.1.0 , ≤ 12.1.11 (semver) Affected: 12.0.0 , ≤ 12.0.37 (semver) Affected: 11.0.0 , ≤ 11.0.31 (semver) Affected: 10.0.0 , ≤ 10.0.31 (semver)

Credits

Arthur Chan David Korczynski Adam Korcz

Show details on NVD website

JSON

To clipboard

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        "metrics": [
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            "other": {
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                "id": "CVE-2026-19204",
                "options": [
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                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-08T15:06:34.664874Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
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        ],
        "providerMetadata": {
          "dateUpdated": "2026-09-08T15:06:46.810Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
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            "Recovery": "NOT_DEFINED",
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    "dateReserved": "2026-08-07T07:33:05.744Z",
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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.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

(CVE-2026-19204)

CVE-2026-19204 (GCVE-0-2026-19204)

Tags

Sightings

Nomenclature

Related by attack behaviour