CVE-2026-33592

An unauthenticated remote attacker can exhaust server memory via the FindServers Discovery Service in open62541. The serverUris field of FindServersRequest is not validated for length or array size. An attacker can declare an arbitrarily large string (up to ~3.9 GB) delivered across intermediate chunks without ever sending the final chunk. The server buffers all chunks in RAM indefinitely until the SecureChannel times out. The attack is pre-session and bypasses all encryption configuration. The issue affects open62541: from 1.4.0 through 1.4.16, from 1.5.0 through 1.5.4, master.

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://github.com/open62541/open62541
https://github.com/open62541/open62541/pull/8142
https://github.com/open62541/open62541/pull/8142/changes/d253818d6c5e870e1db0e360b18138c8bdc809ae

Configurations

No configuration.

History

25 Oct 2026, 21:10

Type	Values Removed	Values Added
Summary		(es) Un atacante remoto no autenticado puede agotar la memoria del servidor a través del servicio de descubrimiento FindServers en open62541. El campo serverUris de FindServersRequest no se valida en cuanto a longitud o tamaño de array. Un atacante puede declarar una cadena de caracteres arbitrariamente grande (hasta ~3.9 GB) entregada a través de fragmentos intermedios sin enviar nunca el fragmento final. El servidor almacena en búfer todos los fragmentos en la RAM indefinidamente hasta que el SecureChannel agota el tiempo de espera. El ataque es pre-sesión y omite toda la configuración de cifrado. El problema afecta a open62541: desde 1.4.0 hasta 1.4.16, desde 1.5.0 hasta 1.5.4, master.

Information

Published : 2026-07-02 08:16

Updated : 2026-10-25 21:10

NVD link : CVE-2026-33592

Mitre link : CVE-2026-33592

CVE.ORG link : CVE-2026-33592

JSON object : View

Products Affected

No product.

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

CWE-789

Memory Allocation with Excessive Size Value

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