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title: Header Injection
collection: mulesoft
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portal_url: https://docs.salesforce.com/mulesoft/current/en-us/release-notes/policies/header-injection-release-notes.md
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product: Release Notes
version: master
keywords: mule, header, injection, policy, release notes
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# Header Injection

> For the full documentation index, see: https://docs.mulesoft.com/llms.txt

## 1.3.3

**October 1, 2026**

### What’s New

- This release updates policy metadata only. There’s no functional change.

## 1.3.1

**May 26, 2022**

### Fixed issues

- Fix policy schema not allowing additional properties via REST API.

## 1.3.0

**May 17, 2022**

### New Features and Enhancements

- First Flex compatible Policy.

- Separated Policy Definition from Policy Implementation. Stronger validations applied to a given
  policy configuration.

## 1.2.1

**Apr 30, 2020**

### Minimum Mule Version

**Mule 4.1.0**

### New Features and Enhancements

- Error handling responses revised for WSDL APIs to be compliant with SOAP 1.1 and 1.2.

- Performance improvements are made to the header manipulation engine.

### Fixed issues

- After a policy was applied, HTTP headers did not follow the RFC 2616 requirement of
  case-sensitivity:

  [https://www.w3.org/Protocols/rfc2616/rfc2616-sec4.html#sec4.2](https://www.w3.org/Protocols/rfc2616/rfc2616-sec4.html#sec4.2).

## 1.2.0

**September 12, 2019**

### Minimum Mule Version

**Mule 4.1.0**

### New Features and Enhancements

- Several performance improvements were introduced in this release.

### Fixed Issues

- An error occurred causing inbound and outbound headers to be set to lower case, ignoring the user
  input.

## 1.1.1

**July 12, 2019**

### Minimum Mule Version

**Mule 4.1.0**

### New Features and Enhancements

- Several performance improvements were introduced in this release.

## 1.1.0

**April 26, 2019**

### Minimum Mule Version

**Mule 4.1.0**

### New Features and Enhancements

- Introduced support for encrypting sensitive information related to the policy. The runtime version
  must be correctly configured to support encryption. Encryption support was introduced in Mule
  Runtime v4.2.0.

- Several performance improvements were introduced in this release.

- Policy weight was reduced.

## 1.0.1

**October 4, 2018**

### Minimum Mule Version

**Mule 4.1.0**

### Fixed Issues

- Policy parameters has an incorrect extra escaping issue.

- An `ExpressionRuntimeException` error occurred when a WSDL proxy received an empty payload, or an
  invalid XML.

## 1.0.0

**March 23, 2018**

### Minimum Mule Version

**4.1.0**

## See Also

- [Header Injection Policy for Mule 4](https://docs.mulesoft.com/gateway/latest/policies-included-header-injection)

- [Header Removal Policy for Mule 4](https://docs.mulesoft.com/gateway/latest/policies-included-header-removal)

- [Known Issues](https://help.salesforce.com/s/issues)