CRLF Injection Affecting github.com/axllent/mailpit/server/internal/smtpd 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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Test your applications- Snyk IDSNYK-GOLANG-GITHUBCOMAXLLENTMAILPITSERVERINTERNALSMTPD-15035878
- published19 Jan 2026
- disclosed18 Jan 2026
- creditOmar Kurt
Introduced: 18 Jan 2026
CVE-2026-23829 Â (opens in a new tab)How to fix?
Upgrade github.com/axllent/mailpit/server/internal/smtpd to version 1.28.3 or higher.
Overview
Affected versions of this package are vulnerable to CRLF Injection via insufficient validation of FROM and TO parameters. An attacker can inject arbitrary SMTP headers or corrupt existing ones by including carriage return characters in email addresses.