CVE-2026-27808

Mailpit is an email testing tool and API for developers. Prior to version 1.29.2, the Link Check API (/api/v1/message/{ID}/link-check) is vulnerable to Server-Side Request Forgery (SSRF). The server performs HTTP HEAD requests to every URL found in an email without validating target hosts or filtering private/internal IP addresses. The response returns status codes and status text per link, making this a non-blind SSRF. In the default configuration (no authentication on SMTP or API), this is fully exploitable remotely with zero user interaction. This is the same class of vulnerability that was fixed in the HTML Check API (CVE-2026-23845 / GHSA-6jxm-fv7w-rw5j) and the screenshot proxy (CVE-2026-21859 / GHSA-8v65-47jx-7mfr), but the Link Check code path was not included in either fix. Version 1.29.2 fixes this vulnerability.

The following products are affected by CVE-2026-27808 vulnerability.

Here, you will find a curated list of external links that provide in-depth information to CVE-2026-27808.

URL	Resource
https://github.com/axllent/mailpit/commit/10ad4df8cc0cd9e51dea1b4410009545eef7fbf5
https://github.com/axllent/mailpit/releases/tag/v1.29.2
https://github.com/axllent/mailpit/security/advisories/GHSA-mpf7-p9x7-96r3