CVE-2026-23845

HIGH EPSS 31.4%
Published Jan 19, 20265mo ago · Modified Jun 17, 20261w ago
7.5 CVSS 3.1
High
Find Similar
Published Jan 19, 2026 5mo ago
Last Modified Jun 17, 2026 1w ago

Description

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 Details

Base Score
7.5
Exploitability
3.9
Impact
3.6
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality High
Integrity None
Availability None

Threat Intelligence

EPSS Exploit Probability
31.4% percentile
Exploit & Patch Status
Public Exploit Known
Patch Available

Weaknesses 1

CWE-918 Server-Side Request Forgery (SSRF) Validation

Affected Products 1

VendorProductVersionRange
axllentmailpit* <1.28.3

References 3

  • github.com https://github.com/axllent/mailpit/commit/1679a0aba592ebc8487a996d37fea8318c984dfe
    Patch
  • github.com https://github.com/axllent/mailpit/releases/tag/v1.28.3
    ProductRelease Notes
  • github.com https://github.com/axllent/mailpit/security/advisories/GHSA-6jxm-fv7w-rw5j
    ExploitVendor Advisory

Remediation

  • github.com https://github.com/axllent/mailpit/commit/1679a0aba592ebc8487a996d37fea8318c984dfe
    Patch