VULNERABILITY INTELLIGENCE

CVE-2026-21859

CVSS score5.8 MEDIUM
EPSS probability0.81%
CISA KEVNot currently listed
Published2026-01-08
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N

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.

Weakness classification

  • security-advisories@github.com: CWE-918

Primary references