CVE-2025-4600 HTTP Request Smuggling in Google Cloud Classic Application Load Balancer due to Improper Chunked Encoding Validation
Attackers could exploit HTTP request smuggling in Google Cloud Classic Application Load Balancer to misinterpret backend requests, potentially accessing or modifying data.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2025-4600?
CVE-2025-4600 is a high-severity vulnerability in Google Cloud Classic Application Load Balancer, published on 16 May 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-444
Which versions are affected by CVE-2025-4600?
It affects 1 product.
Products include Google Application Load Balancer.
How do I fix CVE-2025-4600?
No fix has been published for CVE-2025-4600 yet. Limit exposure of the affected software until one is available.
Is CVE-2025-4600 being exploited?
There is no known exploitation of CVE-2025-4600 in the wild and no public exploit code.
Sources
Also known as GHSA-crqj-898f-x3m2.