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Details of issue NIXPKGS-2026-0045

NIXPKGS-2026-0045
published on 19 Jan 2026
updated 3 days, 2 hours ago by @LeSuisse Activity log
  • Created automatic suggestion
  • @LeSuisse accepted as draft
  • @LeSuisse published on GitHub
Mailpit has SMTP Header Injection via Regex Bypass

Mailpit is an email testing tool and API for developers. Prior to version 1.28. Mailpit's SMTP server is vulnerable to Header Injection due to an insufficient Regular Expression used to validate `RCPT TO` and `MAIL FROM` addresses. An attacker can inject arbitrary SMTP headers (or corrupt existing ones) by including carriage return characters (`\r`) in the email address. This header injection occurs because the regex intended to filter control characters fails to exclude `\r` and `\n` when used inside a character class. Version 1.28.3 fixes this issue.

Affected products

mailpit
  • ==< 1.28.3

Matching in nixpkgs

Package maintainers: 1