CVE-2026-23845

Mailpit is an email testing tool and API for developers. Versions prior to 1.28.3 are vulnerable to Server-Side Request Forgery (SSRF) via HTML Check CSS Download. The HTML Check feature (`/api/v1/message/{ID}/html-check`) is designed to analyze HTML emails for compatibility. During this process, the `inlineRemoteCSS()` function automatically downloads CSS files from external `<link rel="stylesheet" href="...">` tags to inline them for testing. Version 1.28.3 fixes the issue.

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/1679a0aba592ebc8487a996d37fea8318c984dfe	Patch
https://github.com/axllent/mailpit/releases/tag/v1.28.3	Product Release Notes
https://github.com/axllent/mailpit/security/advisories/GHSA-6jxm-fv7w-rw5j	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-01-19 19:16

Updated : 2026-02-05 18:35

NVD link : CVE-2026-23845

Mitre link : CVE-2026-23845

CVE.ORG link : CVE-2026-23845

JSON object : View

Products Affected

axllent

mailpit

CWE

CWE-918

Server-Side Request Forgery (SSRF)

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