---
title: ASE generated error messages for blocked requests
description: The API Security Enforcer (ASE) blocks certain requests based on application programming interface (API) Mapping or API Behavioral Security (ABS)-detected attacks. For these blocked requests, it sends a standard error message back to the client.
component: pingintelligence
version: 5.1
page_id: pingintelligence:api_security_enforcer:pingintelligence_ase_error_messages_blocked_requests
canonical_url: https://docs.pingidentity.com/pingintelligence/5.1/api_security_enforcer/pingintelligence_ase_error_messages_blocked_requests.html
revdate: May 28, 2024
---

# ASE generated error messages for blocked requests

The API Security Enforcer (ASE) blocks certain requests based on application programming interface (API) *(tooltip: \<div class="paragraph">
\<p>A specification of interactions available for building software to access an application or service.\</p>
\</div>)* Mapping or API Behavioral Security (ABS)-detected attacks. For these blocked requests, it sends a standard error message back to the client.

After receiving ASE access logs and API JSON configuration files, ABS applies AI algorithms to track API connections and detect attacks. If `enable_abs_attack` is `true`, ABS sends deny list to ASE, which blocks client identifiers, such as API keys, usernames, cookie, IP address, and OAuth token on the list.

![A diagram of ABS AI-based security.](../../5.2/_images/nhg1564009020141.png)