CVE-2025-4600

HTTP Request Smuggling in Google Cloud Classic Application Load Balancer due to Improper Chunked Encoding Validation

HIGH
7.5
CVSS Score
Published: May 16, 2025 at 01:47 PM UTC
Updated: June 17, 2026 at 09:33 AM UTC
2 products affected across 2 vendorsApplication Load BalancerClassic Application Load Balancer

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Severity
HIGH7.5
Exploit prediction
EPSS 0.2%
SSVC
No known exploit

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 2025-4-26
Affected range stops below 2025-4-26, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
HIGH
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-444

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