Vulnerability · Published Feb 25, 2026 · Assigned by GitHub_M
CVE-2026-27808Mailpit is Vulnerable to Server-Side Request Forgery (SSRF) via Link Check API
Medium 5.8
In plain English
A medium-severity server-side request forgery in mailpit from axllent. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 45% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/axllent/mailpit | 1.29.2 | GHSA-mpf7-p9x7-96r3 |
| Go | github.com/axllent/mailpit | 1.29.2 | GO-2026-4558 |
Affected products (as reported)
Weakness: CWE-918 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N
References
- https://github.com/axllent/mailpit/security/advisories/GHSA-mpf7-p9x7-96r3 x_refsource_CONFIRM
- https://github.com/axllent/mailpit/commit/10ad4df8cc0cd9e51dea1b4410009545eef7fbf5 x_refsource_MISC
- https://github.com/axllent/mailpit/releases/tag/v1.29.2 x_refsource_MISC