CVE-2026-67446

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.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/axllent/mailpit/commit/6bcb6337838b542d53c348e38c7977f569b6db35
https://github.com/axllent/mailpit/releases/tag/v1.30.4
https://github.com/axllent/mailpit/security/advisories/GHSA-75mr-qw9x-3r39
https://github.com/axllent/mailpit/security/advisories/GHSA-75mr-qw9x-3r39

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-20 21:17

Updated : 2026-08-21 15:16

NVD link : CVE-2026-67446

Mitre link : CVE-2026-67446

CVE.ORG link : CVE-2026-67446

JSON object : View

Products Affected

No product.

CWE

CWE-400

Uncontrolled Resource Consumption

CWE-770

Allocation of Resources Without Limits or Throttling

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