CVE-2026-45713

Mailpit is an email testing tool and API for developers. Prior to version 1.30.0, the Mailpit SMTP server has a Server.MaxSize int field that controls the maximum allowed DATA payload size, but the field is never assigned anywhere outside test code, leaving it at Go's zero value (0 ⇒ "no limit"). The same applies to the HTTP /api/v1/send endpoint, whose request body is decoded with json.NewDecoder(r.Body) and no http.MaxBytesReader. Because Mailpit's default listeners bind [::]:1025 (SMTP) and [::]:8025 (HTTP), with no authentication required on either, a single network-reachable attacker can push an arbitrarily large message into Mailpit and watch RAM consumption spike with a ~7-10× amplification factor (raw frame → enmime envelope tree → search-text index → zstd-encoded write to SQLite). Repeating the attack — or running it concurrently from multiple connections — drives the process to OOM-kill. Version 1.30.0 contains a patch.
Configurations

Configuration 1 (hide)

cpe:2.3:a:axllent:mailpit:*:*:*:*:*:*:*:*

History

28 Jul 2026, 15:24

Type Values Removed Values Added
CPE cpe:2.3:a:axllent:mailpit:*:*:*:*:*:*:*:*
First Time Axllent mailpit
Axllent
References () https://github.com/axllent/mailpit/releases/tag/v1.30.0 - () https://github.com/axllent/mailpit/releases/tag/v1.30.0 - Release Notes
References () https://github.com/axllent/mailpit/security/advisories/GHSA-fpxj-m5q8-fphw - () https://github.com/axllent/mailpit/security/advisories/GHSA-fpxj-m5q8-fphw - Exploit, Vendor Advisory

20 Jul 2026, 17:17

Type Values Removed Values Added
References () https://github.com/axllent/mailpit/security/advisories/GHSA-fpxj-m5q8-fphw - () https://github.com/axllent/mailpit/security/advisories/GHSA-fpxj-m5q8-fphw -

20 Jul 2026, 16:17

Type Values Removed Values Added
New CVE

Information

Published : 2026-07-20 16:17

Updated : 2026-07-28 15:24


NVD link : CVE-2026-45713

Mitre link : CVE-2026-45713

CVE.ORG link : CVE-2026-45713


JSON object : View

Products Affected

axllent

  • mailpit
CWE
CWE-400

Uncontrolled Resource Consumption

CWE-770

Allocation of Resources Without Limits or Throttling