CVE-2026-21859

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.

CVSS v3 5.8 MEDIUM

5.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/axllent/mailpit/commit/3b9b470c093b3d20b7d751722c1c24f3eed2e19d	Patch
https://github.com/axllent/mailpit/security/advisories/GHSA-8v65-47jx-7mfr	Exploit Vendor Advisory
https://github.com/axllent/mailpit/security/advisories/GHSA-8v65-47jx-7mfr	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:axllent:mailpit:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-01-08 00:16

Updated : 2026-02-02 19:16

NVD link : CVE-2026-21859

Mitre link : CVE-2026-21859

CVE.ORG link : CVE-2026-21859

JSON object : View

Products Affected

axllent

mailpit

CWE

CWE-918

Server-Side Request Forgery (SSRF)

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