Vulnerability Description
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 Score
MEDIUM
Related Weaknesses (CWE)
References
- https://github.com/axllent/mailpit/commit/6bcb6337838b542d53c348e38c7977f569b6db
- 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
FAQ
What is CVE-2026-67446?
CVE-2026-67446 is a vulnerability with a CVSS score of 5.3 (MEDIUM). 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 mem...
How severe is CVE-2026-67446?
CVE-2026-67446 has been rated MEDIUM with a CVSS base score of 5.3/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-67446?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.