Description
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.
Published: 2026-09-07
Score: 8.7 High
EPSS: n/a
KEV: No
Impact: n/a
Action: n/a
AI Analysis

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Remediation

No vendor fix or workaround currently provided.

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Tracking

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Advisories

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History

Mon, 07 Sep 2026 13:45:00 +0000

Type Values Removed Values Added
Title Jetty WebSocket Frame Memory Exhaustion via Unknown Opcode and Large Payload
First Time appeared Eclipse
Eclipse jetty
Vendors & Products Eclipse
Eclipse jetty

Mon, 07 Sep 2026 10:45:00 +0000

Type Values Removed Values Added
Description 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.
Weaknesses CWE-770
CWE-789
References
Metrics cvssV4_0

{'score': 8.7, 'vector': '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'}

Subscriptions

Eclipse Jetty
cve-icon MITRE

Status: PUBLISHED

Assigner: eclipse

Published:

Updated: 2026-09-07T10:19:24.186Z

Reserved: 2026-08-07T07:33:05.744Z

Link: CVE-2026-19204

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-09-07T11:17:20.600

Modified: 2026-09-07T11:17:20.600

Link: CVE-2026-19204

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-09-07T13:30:16Z

Weaknesses
  • CWE-770

    Allocation of Resources Without Limits or Throttling

  • CWE-789

    Memory Allocation with Excessive Size Value