---
id: CVE-2026-67446
title: Mailpit is an email testing tool and API for developers
summary: >-
  Mailpit is an email testing tool and API for developers. Prior to 1.30.4,
  Mailpit decodes attacker-supplied image attachments into a full raster before
  checking decoded dimensions, pixel count, or memory use in the GET
  /api/v1/message/{i…
severity: medium
cvss: 5.3
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L'
cwe:
  - CWE-400
  - CWE-770
vendor: axllent
product: github.com/axllent/mailpit
affected:
  - github.com/axllent/mailpit < 1.30.4
patched:
  - github.com/axllent/mailpit 1.30.4
published: '2026-08-20'
updated: '2026-09-18'
sourceUpdated: '2026-09-18T20:09:01.757'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-67446'
references:
  - url: >-
      https://github.com/axllent/mailpit/commit/6bcb6337838b542d53c348e38c7977f569b6db35
    label: security-advisories@github.com
  - url: 'https://github.com/axllent/mailpit/releases/tag/v1.30.4'
    label: security-advisories@github.com
  - url: 'https://github.com/axllent/mailpit/security/advisories/GHSA-75mr-qw9x-3r39'
    label: security-advisories@github.com
  - url: 'https://github.com/axllent/mailpit/security/advisories/GHSA-75mr-qw9x-3r39'
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-67446'
  - url: 'https://github.com/axllent/mailpit'
  - url: 'https://github.com/advisories/GHSA-75mr-qw9x-3r39'
tags:
  - nvd
  - osv
  - go
  - ghsa
  - score-dispute
epss: 0.00371
epssPercentile: 0.31025
aliases:
  - GHSA-75mr-qw9x-3r39
  - GO-2026-6359
ecosystem: go
scores:
  nvd: 5.3
  osv: 7.5
ingestedAt: '2026-09-02T23:52:23.098Z'
---

## Overview

Mailpit is an email testing tool and API for developers. Prior to 1.30.4, Mailpit decodes attacker-supplied image attachments into a full raster before checking decoded dimensions, pixel count, or memory use in the GET /api/v1/message/{id}/part/{partID}/thumb endpoint. The Thumbnail handler in server/apiv1/thumbnails.go obtains attachment bytes through storage.GetAttachmentPart(), accepts image/* content, and calls imaging.Decode() with AutoOrientation before imaging.Fill() scales the image to 180 by 120 pixels. A compact image declaring very large dimensions can therefore consume disproportionately large memory and CPU, and opening the message UI can trigger the same endpoint through server/ui-src/components/message/MessageAttachments.vue. This can degrade availability when an unauthenticated client can store the crafted attachment and reach the web API. This issue is fixed in version 1.30.4.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Package advisory (CVE-2026-67446)

Affected packages:

- `github.com/axllent/mailpit < 1.30.4`

Patched in:

- `github.com/axllent/mailpit 1.30.4`

Source: https://osv.dev/vulnerability/GHSA-75mr-qw9x-3r39