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

No history.

Information

Published : 2025-05-16 14:15

Updated : 2025-09-26 17:18

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-444

Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

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