---
id: "CVE-2026-119415"
kind: "vulnerability"
aliases: ["CVE-2026-119415"]
title: "CakePHP: unsanitized MIME headers let attackers inject extra multipart content"
severity: "medium"
cvss: 6.3
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["cakephp", "email", "http-client", "package", "php"]
not_affected_if: ["fixed-attachment-types", "no-user-input-in-attachments"]
published_at: "2026-10-30T12:16:37+00:00"
first_seen_at: "2026-10-30T12:30:23+00:00"
updated_at: "2026-10-30T12:32:46+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-119415", "first_seen_at": "2026-10-30T12:30:23+00:00"}]
---

# CakePHP: unsanitized MIME headers let attackers inject extra multipart content

CakePHP through 5.4.3 does not strip CR/LF characters from attachment Content-Type and Content-ID values in FormDataPart. An attacker who controls those values can add arbitrary MIME part headers or content to outgoing email or HTTP multipart requests.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Find the CakePHP version with `vendor/bin/cake --version` or check `cakephp/cakephp` in `composer.lock`.
- Look for calls to `Message::setAttachments()` or multipart HTTP client data that take user-supplied MIME types or Content-IDs.

## Timeline

- 2026-10-30T12:30:23+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-119415

## From the sources

CakePHP through 5.4.3 contains a header injection vulnerability in FormDataPart that allows attackers to inject MIME part headers via unsanitized Content-Type and Content-ID values. Attackers can supply CR/LF sequences in attachment MIME types or Content-IDs passed to Message::setAttachments() or HTTP client multipart data to add arbitrary headers or content.

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