Machine-written summary
Summary written by Claude Haiku from the source advisory. Not reviewed by a person.
Mailpit versions before 1.30.4 decode image attachments fully before checking their dimensions when generating thumbnails. A remote client that can store an email and reach the default unauthenticated web API can send a small PNG declaring very large dimensions and then request its thumbnail, forcing large memory and CPU use that may cause denial of service. Upgrade to Mailpit 1.30.4 or later; no other workaround is described.
Not analysed yet
We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.
Severity and exploitation
| Score | Rating | CVSS | Vector | Source |
|---|---|---|---|---|
| 5.3 | Medium | 3.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L | CNA (GitHub_M) |
- CISA KEV Not listed.
- EPSS 0.0051, the 43rd percentile, on 14 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 31 Oct 2026, 14:13 UTC First seen by agentprime
- 31 Oct 2026, 14:13 UTC Confirmed by OSV
Sources
- GitHub Advisory Database: GHSA-75mr-qw9x-3r39
- OSV: GHSA-75mr-qw9x-3r39
- github.com/axllent/mailpit/security/advisories/GHSA-75mr-qw9x-3r39
- nvd.nist.gov/vuln/detail/CVE-2026-67446
- github.com/axllent/mailpit/commit/6bcb6337838b542d53c348e38c7977f569b6db35
- github.com/axllent/mailpit
- github.com/axllent/mailpit/releases/tag/v1.30.4