GHSA-8v65-47jx-7mfr: github.com/axllent/mailpit (CVE-2026-21859)

Mailpit Proxy Endpoint has Server-Side Request Forgery (SSRF) vulnerability in github.com/axllent/mailpit

CVSS 5.8 MediumEPSS 0.0081 · 57th percentile

Published by the GitHub Advisory Database at 12 Jan 2026, 17:39 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

Package	Ecosystem	Affected	Fixed in
github.com/axllent/mailpit	Go	<1.28.1	1.28.1

Identifiers

GHSA-8v65-47jx-7mfr · CVE-2026-21859 · GO-2026-4284

Weakness (CWE)

CWE-918

Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

Mailpit versions before 1.28.1 are affected by a Server-Side Request Forgery (SSRF) vulnerability in its proxy endpoint. The source gives few details on the conditions required or the scope of requests an attacker could make. Upgrade github.com/axllent/mailpit to version 1.28.1 or later.

Written 10 Nov 2026.

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
5.8	Medium	3.1	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N	CNA (GitHub_M)

CISA KEV Not listed.
EPSS 0.0081, the 57th percentile, on 15 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

This record came from the full history of the GitHub Advisory Database, published 12 Jan 2026. New records show when each source confirmed them.

Sources

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.