Cis Apache 10.3

---
name: cis-apache-10.3
description: "Ensure the LimitRequestFieldsize Directive is Set to 1024 or Less"
category: cis-apache
version: "3.6.0"
author: cyberstrike-official
tags: [cis, apache, linux, request-limits, hardening]
cis_id: "10.3"
cis_benchmark: "CIS Apache HTTP Server 2.2 Benchmark v3.6.0"
tech_stack: [linux, apache]
cwe_ids: []
chains_with: []
prerequisites: []
severity_boost: {}
---

# Ensure the LimitRequestFieldsize Directive is Set to 1024 or Less

## Description

The `LimitRequestFieldSize` limits the number of bytes that will be allowed in an HTTP request header. It is recommended that the `LimitRequestFieldSize` directive be set to `1024` or less.

## Rationale

By limiting of the size of request headers is helpful so that the web server can prevent an unexpectedly long or large value from being passed to exploit a potentially vulnerable program. Of course, the underlying dependency is that we need to set the limits high enough to not interfere with any one application on the server, while setting them low enough to be of value in protecting the applications. Since the configuration directives are available only at the server configuration level, it is not possible to tune the value for different portions of the same web server. Please read the Apache documentation carefully, as these requests may interfere with the expected functionality of some web applications.

## Impact

None documented

## Audit Procedure

Perform the following steps to determine if the recommended state is implemented:

Verify that the `LimitRequestFieldSize` directive is in the Apache configuration and has a value of `1024` or less.

## Remediation

Perform the following to implement the recommended state:

Add or modify the `LimitRequestFieldSize` directive in the Apache configuration to have a value of `1024` or less.

```
LimitRequestFieldsize 1024
```

## Default Value

```
LimitRequestFieldSize 8190
```

## References

1. https://httpd.apache.org/docs/2.2/mod/core.html#limitrequestfieldsize

## CIS Controls

**Version 6**

9 Limitation and Control of Network Ports, Protocols, and Services
Limitation and Control of Network Ports, Protocols, and Services

**Version 7**

5.1 Establish Secure Configurations
Maintain documented, standard security configuration standards for all authorized
operating systems and software.

## Profile

Level 2 | Scored