CVE-2026-40303

zrok is software for sharing web services, files, and network resources. Prior to version 2.0.1, endpoints.GetSessionCookie parses an attacker-supplied cookie chunk count and calls make([]string, count) with no upper bound before any token validation occurs. The function is reached on every request to an OAuth-protected proxy share, allowing an unauthenticated remote attacker to trigger gigabyte-scale heap allocations per request, leading to process-level OOM termination or repeated goroutine panics. Both publicProxy and dynamicProxy are affected. Version 2.0.1 patches the issue.

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/openziti/zrok/releases/tag/v2.0.1	Release Notes
https://github.com/openziti/zrok/security/advisories/GHSA-cpf9-ph2j-ccr9	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:netfoundry:zrok:*:*:*:*:*:*:*:*

History

26 Oct 2026, 22:10

Type	Values Removed	Values Added
Summary		(es) zrok es un software para compartir servicios web, archivos y recursos de red. Antes de la versión 2.0.1, endpoints.GetSessionCookie analiza un recuento de fragmentos de cookie proporcionado por un atacante y llama a make([]string, count) sin un límite superior antes de que ocurra cualquier validación de token. Se accede a la función en cada solicitud a un recurso compartido de proxy protegido por OAuth, lo que permite a un atacante remoto no autenticado activar asignaciones de memoria heap a escala de gigabytes por solicitud, lo que lleva a la terminación OOM a nivel de proceso o a pánicos repetidos de goroutine. Tanto publicProxy como dynamicProxy se ven afectados. La versión 2.0.1 corrige el problema.

Information

Published : 2026-04-17 21:16

Updated : 2026-10-26 22:10

NVD link : CVE-2026-40303

Mitre link : CVE-2026-40303

CVE.ORG link : CVE-2026-40303

JSON object : View

Products Affected

netfoundry

zrok

CWE

CWE-400

Uncontrolled Resource Consumption

CWE-789

Memory Allocation with Excessive Size Value

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