Affected: Maven: io.netty:netty-codec-stomp

# Security Vulnerability Report: STOMP CONNECT Frame Header Injection in Netty

## 1. Vulnerability Summary

| Field | Value | |-------|-------| | **Product** | Netty | | **Version** | 4.2.12.Final (and all prior versions with codec-stomp) | | **Component** | `io.netty.handler.codec.stomp.StompSubframeEncoder` | | **Vulnerability Type** | CWE-93: Improper Neutralization of CRLF Sequences / CWE-113: Improper Neutralization of CRLF in HTTP Headers | | **Impact** | STOMP Header Injection / Authentication Bypass | | **CVSS 3.1 Score** | **6.5 (Medium)** | | **CVSS 3.1 Vector** | `CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N` | | **Attack Vector** | Network | | **Attack Complexity** | Low | | **Privileges Required** | Low | | **User Interaction** | None | | **Scope** | Unchanged | | **Confidentiality Impact** | None | | **Integrity Impact** | High | | **Availability Impact** | None |

## 2. Affected Components

- `io.netty.handler.codec.stomp.StompSubframeEncoder` — `encodeHeaders()` method (lines 174-200) - `io.netty.handler.codec.stomp.StompSubframeEncoder` — `shouldEscape()` method (lines 214-216)

## 3. Vulnerability Description

The Netty STOMP codec encoder (`StompSubframeEncoder`) intentionally skips the `escape()` function for `CONNECT` and `CONNECTED` commands. This means that newline characters (`\n`) in header values of CONNECT frames are written directly to the output, allowing an attacker to inject additional STOMP headers.

### Root Cause

In `StompSubframeEncoder.j…