Server-side Request Forgery (SSRF) Affecting github.com/axllent/mailpit/internal/htmlcheck package, versions <1.28.3
Threat Intelligence
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Start learning- Snyk IDSNYK-GOLANG-GITHUBCOMAXLLENTMAILPITINTERNALHTMLCHECK-15038742
- published20 Jan 2026
- disclosed19 Jan 2026
- creditMehmet INCE
Introduced: 19 Jan 2026
CVE-2026-23845 Â (opens in a new tab)How to fix?
Upgrade github.com/axllent/mailpit/internal/htmlcheck to version 1.28.3 or higher.
Overview
Affected versions of this package are vulnerable to Server-side Request Forgery (SSRF) in the inlineRemoteCSS function during the HTML email analysis process. An attacker can cause the server to make arbitrary HTTP requests to external resources by supplying crafted HTML emails containing external <link rel="stylesheet" href="..."> tags.