CVE-2026-5680
Received
Received - Intake
Undertow WebSocket DoS via Permessage-Deflate
Vulnerability report for CVE-2026-5680, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-08-27
Last updated on: 2026-08-27
Assigner: redhat-SADP
Description
Description
A flaw was found in Undertow. A remote attacker could exploit this vulnerability by sending specially crafted WebSocket messages with permessage-deflate negotiated. This could lead to excessive memory consumption due to the PerMessageDeflateFunction.largerBuffer() method using exponential doubling, resulting in a Denial of Service (DoS) for the affected application.
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| undertow | undertow | * |
| redhat | undertow | * |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-770 | The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated. |
