CVE-2026-21859

MEDIUM EXPLOITED NUCLEI

Axllent Mailpit < 1.28.1 - SSRF

Title source: rule

Description

Mailpit is an email testing tool and API for developers. Versions 1.28.0 and below have a Server-Side Request Forgery (SSRF) vulnerability in the /proxy endpoint, allowing attackers to make requests to internal network resources. The /proxy endpoint validates http:// and https:// schemes, but it does not block internal IP addresses, enabling attackers to access internal services and APIs. This vulnerability is limited to HTTP GET requests with minimal headers. The issue is fixed in version 1.28.1.

Nuclei Templates (1)

Mailpit < 1.28.3 - Server-Side Request Forgery

HIGHVERIFIEDby omarkurt

Shodan: title:"Mailpit"

FOFA: title="Mailpit"

References (2)

[Patch] https://github.com/axllent/mailpit/commit/3b9b470c093b3d20b7d751722c1c24f3eed2e19d

View Patch ZIP pw:eip

[Exploit, Vendor Advisory] https://github.com/axllent/mailpit/security/advisories/GHSA-8v65-47jx-7mfr

Scores

CVSS v3 5.8

EPSS 0.0102

EPSS Percentile 77.3%

Attack Vector NETWORK

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N

Details

VulnCheck KEV 2026-02-11

CWE

CWE-918

Status published

Products (2)

axllent/mailpit < 1.28.1

axllent/mailpit 0 - 1.28.1Go

Published Jan 08, 2026

Tracked Since Feb 18, 2026