CVE-2026-41319

Katalog CVE

CVSS 5.9 · Medium EPSS 0,33%

Kerentanan Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection') pada jstedfast mailkit. Skor CVSS 3.1 5.9 (Medium) menurut NVD.

Deskripsi (NVD)

MailKit is a cross-platform mail client library built on top of MimeKit. A STARTTLS Response Injection vulnerability in versions prior to 4.16.0 allows a Man-in-the-Middle attacker to inject arbitrary protocol responses across the plaintext-to-TLS trust boundary, enabling SASL authentication mechanism downgrade (e.g., forcing PLAIN instead of SCRAM-SHA-256). The internal read buffer in `SmtpStream`, `ImapStream`, and `Pop3Stream` is not flushed when the underlying stream is replaced with `SslStream` during STARTTLS upgrade, causing pre-TLS attacker-injected data to be processed as trusted post-TLS responses. Version 4.16.0 patches the issue.

Rincian

Terbit di NVD

24 April 2026

Terakhir diubah

17 Juni 2026

Status NVD

Analyzed

CVSS 3.1

5.9 (Medium), sumber NVD
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N · uraikan di kalkulator

Jenis kelemahan (CWE)

CWE-74: Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

EPSS (30 hari)

0,33% peluang dieksploitasi; lebih tinggi dari 24,4% CVE lain

Produk dan versi terdampak

> Data dari konfigurasi CPE di NVD.

Referensi dan perbaikan

• https://github.com/jstedfast/MailKit/security/advisories/GHSA-9j88-vvj5-vhgr exploit · advisory vendor