CVE-2025-4600

A request smuggling vulnerability existed in the Google Cloud Classic Application Load Balancer due to improper handling of chunked-encoded HTTP requests. This allowed attackers to craft requests that could be misinterpreted by backend servers. The issue was fixed by disallowing stray data after a chunk, and is no longer exploitable. No action is required as Classic Application Load Balancer service after 2025-04-26 is not vulnerable.

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 HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://cloud.google.com/support/bulletins#gcp-2025-027	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:google:application_load_balancer:*:*:*:*:*:*:*:*

History

29 Jul 2025, 13:03

Type	Values Removed	Values Added
Summary		(es) Existía una vulnerabilidad de contrabando de solicitudes en Google Cloud Classic Application Load Balancer debido a la gestión incorrecta de solicitudes HTTP con codificación fragmentada. Esto permitía a los atacantes manipular solicitudes que los servidores backend podían malinterpretar. El problema se solucionó deshabilitando los datos dispersos después de un fragmento y ya no es explotable. No se requiere ninguna acción, ya que el servicio del balanceador de carga de aplicaciones clásico después del 26/04/2025 no es vulnerable.
References	~~() https://cloud.google.com/support/bulletins#gcp-2025-027 -~~	() https://cloud.google.com/support/bulletins#gcp-2025-027 - Vendor Advisory
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.5
CPE		cpe:2.3:a:google:application_load_balancer::::::::
First Time		Google Google application Load Balancer

16 May 2025, 14:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2025-05-16 14:15

Updated : 2025-07-29 13:03

NVD link : CVE-2025-4600

Mitre link : CVE-2025-4600

CVE.ORG link : CVE-2025-4600

JSON object : View

Products Affected

google

application_load_balancer

CWE

CWE-20

Improper Input Validation

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