CVE-2026-15565

A flaw was found in Undertow. A remote attacker can cause Out of Memory on websockets endpoint without authentication on any @ServerEndpoint class that has any @OnMessage method. This allows an attacker to cause Denial of Service attack without authentication and using only a standard WebSocket handshake.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/errata/RHSA-2026:53806
https://access.redhat.com/security/cve/CVE-2026-15565
https://bugzilla.redhat.com/show_bug.cgi?id=2490628

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-11 09:17

Updated : 2026-08-24 12:16

NVD link : CVE-2026-15565

Mitre link : CVE-2026-15565

CVE.ORG link : CVE-2026-15565

JSON object : View

Products Affected

No product.

CWE

CWE-120

Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

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