CVE-2026-41319 MailKit has STARTTLS Response Injection via unflushed stream buffer that enables SASL mechanism downgrade

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...

CVE-2026-41319

Summary (CVE-2026-41319) MailKit (MimeKit-based) exposes a STARTTLS vulnerability where the internal read buffers of SmtpStream, ImapStream, and Pop3Stream are not flushed when upgrading to TLS with SslStream. This allows pre-TLS attacker-injected data to be treated as post-TLS, enabling a MITM-b...

MailKit 注入漏洞

MailKit is a cross-platform email client library developed by Jeffrey Stedfast. Versions of MailKit prior to 4.16.0 had an injection vulnerability. This vulnerability stemmed from STARTTLS response injection, which allowed man-in-the-middle attackers to inject arbitrary protocol responses, thereb...

MailKit has STARTTLS Response Injection via unflushed stream buffer that enables SASL mechanism downgrade

Summary A STARTTLS Response Injection vulnerability in MailKit 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...

MiracleLinux 4 : thunderbird-78.7.0-1.0.1.AXS4 (AXSA:2021-1432:01)

The remote MiracleLinux 4 host has a package installed that is affected by multiple vulnerabilities as referenced in the AXSA:2021-1432:01 advisory. Mozilla: Cross-origin information leakage via redirected PDF requests CVE-2021-23953 Mozilla: Type confusion when using logical assignment operators...

MiracleLinux 3 : postfix-2.3.3-2.10.AXS3 (AXSA:2011-150:02)

The remote MiracleLinux 3 host has packages installed that are affected by multiple vulnerabilities as referenced in the AXSA:2011-150:02 advisory. Postfix is a Mail Transport Agent MTA, supporting LDAP, SMTP AUTH SASL, TLS Security issues fixed with this release: CVE-2008-2937 Postfix 2.5 before...

TencentOS Server 3: dovecot (TSSA-2022:0239)

The version of Tencent Linux installed on the remote TencentOS Server 3 host is prior to tested version. It is, therefore, affected by a vulnerability as referenced in the TSSA-2022:0239 advisory. Package updates are available for TencentOS Server 3 that fix the following vulnerabilities:...

aiosmptd 安全漏洞

aiosmtpd is an asyncio-based SMTP server. A security vulnerability exists in aiosmptd versions prior to 1.4.6, which stems from the presence of STARTTLS unencrypted command injection...

SUSE CVE-2021-33515

The submission service in Dovecot before 2.3.15 allows STARTTLS command injection in lib-smtp. Sensitive information can be redirected to an attacker-controlled address...

The submission service in Dovecot before 2.3.15 allows STARTTLS command injection in lib-smtp. Sensitive information can be redirected to an attacker-controlled address.

...

SUSE-SU-2021:3351-1 Security update for curl

This update for curl fixes the following issues: - CVE-2021-22947: Fixed STARTTLS protocol injection via MITM bsc1190374. - CVE-2021-22946: Fixed protocol downgrade required TLS bypassed bsc1190373...

SUSE-SU-2021:14807-1 Security update for curl

This update for curl fixes the following issues: - CVE-2021-22947: Fixed STARTTLS protocol injection via MITM bsc1190374. - CVE-2021-22946: Fixed protocol downgrade required TLS bypassed bsc1190373...

OPENSUSE-SU-2021:1225-1 Security update for dovecot23

This update for dovecot23 fixes the following issues: Update dovecot to version 2.3.15 jscSLE-19970: Security issues fixed: - CVE-2021-29157: Dovecot does not correctly escape kid and azp fields in JWT tokens. This may be used to supply attacker controlled keys to validate tokens, if attacker has...

CVE-2020-15955

In s/qmail through 4.0.07, an active MitM can inject arbitrary plaintext commands into a STARTTLS encrypted session between an SMTP client and s/qmail. This allows e-mail messages and user credentials to be sent to the MitM attacker...

UBUNTU-CVE-2021-38371

The STARTTLS feature in Exim through 4.94.2 allows response injection buffering during MTA SMTP sending...

DEBIAN-CVE-2021-33515

The submission service in Dovecot before 2.3.15 allows STARTTLS command injection in lib-smtp. Sensitive information can be redirected to an attacker-controlled address...

USN-4993-1 dovecot vulnerabilities

Kirin discovered that Dovecot incorrectly escaped kid and azp fields in JWT tokens. A local attacker could possibly use this issue to validate tokens using arbitrary keys. This issue only affected Ubuntu 20.10 and Ubuntu 21.04. CVE-2021-29157 Fabian Ising and Damian Poddebniak discovered that...

SUSE: Security Advisory (SUSE-SU-2012:1147-1)

The remote host is missing an update for the SPDX-FileCopyrightText: 2021 Greenbone AG Some text descriptions might be excerpted from a referenced sources, and are Copyright C by the respective right holders. SPDX-License-Identifier: GPL-2.0-only ifdescription...

SUSE-SU-2020:1771-1 Security update for mutt

This update for mutt fixes the following issues: - CVE-2020-14954: Fixed a response injection due to a STARTTLS buffering issue which was affecting IMAP, SMTP, and POP3 bsc1173197. - CVE-2020-14093: Fixed a potential IMAP Man-in-the-Middle attack via a PREAUTH response bsc1172906, bsc1172935. -...

SuSE 11.2 Security Update : inn (SAT Patch Number 6774)

A STARTTLS injection issue has been fixed in inn. CVE-2012-3523 was assigned to this issue. %NASLMINLEVEL 70300 C Tenable Network Security, Inc. The descriptive text and package checks in this plugin were extracted from SuSE 11 update information. The text itself is copyright C Novell, Inc...