Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection') Affecting mailkitlite package, versions [,4.16.0)
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-DOTNET-MAILKITLITE-16115138
- published21 Apr 2026
- disclosed18 Apr 2026
- creditROCmertakdag
Introduced: 18 Apr 2026
NewCVE-2026-41319 (opens in a new tab)How to fix?
Upgrade MailKitLite to version 4.16.0 or higher.
Overview
Affected versions of this package are vulnerable to Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection') via the internal stream buffers (SmtpStream, ImapStream, and Pop3Stream) not being flushed during the STARTTLS upgrade process. An attacker can manipulate authentication mechanisms and protocol capabilities by injecting crafted protocol responses across the plaintext-to-TLS boundary using a man-in-the-middle position.