RHEL 8 : dovecot (RHSA-2026:46381)

The remote Redhat Enterprise Linux 8 host has a package installed that is affected by a vulnerability as referenced in the RHSA-2026:46381 advisory. Dovecot is an IMAP server for Linux and other UNIX-like systems, written primarily with security in mind. It also contains a small POP3 server, and...

ruby/net-imap: ruby: Net::IMAP: IMAP Command Injection via Symbol Arguments

A flaw was found in Net::IMAP, a Ruby library that provides Internet Message Access Protocol IMAP client functionality. This vulnerability allows a remote attacker to inject arbitrary IMAP commands. This is achieved by passing specially crafted symbol arguments to IMAP commands. Successful...

AlmaLinux 8 : ruby:3.3 (ALSA-2026:33515)

The remote AlmaLinux 8 host has packages installed that are affected by multiple vulnerabilities as referenced in the ALSA-2026:33515 advisory. ruby: net-imap: Net::IMAP: Denial of Service via crafted IMAP responses CVE-2026-42245 ruby/net-imap: ruby: Net::IMAP: IMAP Command Injection via Symbol...

AlmaLinux 9 : ruby:3.3 (ALSA-2026:33576)

The remote AlmaLinux 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the ALSA-2026:33576 advisory. ruby: net-imap: Net::IMAP: Denial of Service via crafted IMAP responses CVE-2026-42245 ruby/net-imap: ruby: Net::IMAP: IMAP Command Injection via Symbol...

ruby: net-imap: Net::IMAP: Denial of Service via crafted IMAP responses

A flaw was found in Net::IMAP, a Ruby library implementing the Internet Message Access Protocol IMAP client functionality. A hostile server can exploit a quadratic time complexity issue in the Net::IMAP::ResponseReader when processing large responses containing numerous string literals. This can...

ruby/net-imap: ruby: Net::IMAP: IMAP Command Injection via Symbol Arguments

A flaw was found in Net::IMAP, a Ruby library that provides Internet Message Access Protocol IMAP client functionality. This vulnerability allows a remote attacker to inject arbitrary IMAP commands. This is achieved by passing specially crafted symbol arguments to IMAP commands. Successful...

net-imap: rubygem-net-imap: Net::IMAP: Denial of Service via malformed command input

A flaw was found in Net::IMAP, a Ruby client library for the Internet Message Access Protocol IMAP. This vulnerability allows a remote attacker to cause a denial of service by sending specially crafted input to certain Net::IMAP commands. When a raw string argument, derived from user-controlled...

Important: ruby:3.3 security update

Ruby is an extensible, interpreted, object-oriented, scripting language. It has features to process text files and to perform system management tasks. Security Fixes: ruby: net-imap: Net::IMAP: Denial of Service via crafted IMAP responses CVE-2026-42245 ruby/net-imap: ruby: Net::IMAP: IMAP Comman...

CVE-2026-56766

Hydra through 9.7, fixed in commit 9cc84c2, contains a stack buffer overflow in NTLM authentication across SMTP, POP3, IMAP, NNTP, HTTP, HTTP-Proxy, and HTTP-Proxy-Urlenum modules when processing malicious NTLM Type-2 challenges. A malicious server can send a crafted NTLM Type-2 challenge with an...

PT-2026-52540

Name of the Vulnerable Software and Affected Versions Hydra versions prior to 9.7 commit 9cc84c2 Description A stack buffer overflow exists in the NTLM authentication process across the SMTP, POP3, IMAP, NNTP, HTTP, HTTP-Proxy, and HTTP-Proxy-Urlenum modules. The issue occurs when the software...

GHSA-C4FP-CXRR-MJ66 Net::IMAP: Denial of Service via incomplete raw argument validation

Summary Several Net::IMAP commands accept a raw string argument which is only validated to prevent CRLF injection and then sent verbatim. If this string is derived from user-controlled input, an attacker can force the next command to be absorbed as a continuation of the first command. This will...

GHSA-8P34-64R3-MWG8 Net::IMAP: Command Injection via non-synchronizing literal in "raw" argument

Several Net::IMAP commands accept a "raw data" argument that is sent verbatim after validation to prevent command injection. However, if a server does not support non-synchronizing literals, it may still be possible to inject arbitrary IMAP commands inside non-synchronizing literals. Details Raw...

PT-2026-48341

Name of the Vulnerable Software and Affected Versions Net::IMAP versions prior to 0.5.15 Net::IMAP versions prior to 0.6.5 Description Several commands in the Net::IMAP Ruby client accept raw string arguments that are only validated to prevent CRLF injection and are then sent verbatim. An incorre...

Astra Linux – Vulnerability in Ruby2.5, JRuby

A issue was discovered in Ruby between versions 2.6.7, 2.7.x up to 2.7.3, and 3.x up to 3.0.1. The Net::IMAP library does not raise an exception when the StartTLS command fails with an unknown response. This may allow man-in-the-middle attackers to bypass TLS protections by leveraging the network...

CLSA-2026-1778250399 dovecot: Fix of CVE-2026-27857

CVE-2026-27857: imap-login: limit IMAP parser open lists to prevent excessive memory usage...

SUSE CVE-2026-42006

An attacker can cause uncontrolled memory usage with excessive bracing over IMAP. The fix in CVE-2026-27857 was incomplete, only blocking one way of doing this, so there was still another way left open. In particular, the fix was for closing braces, but you could still use open braces to bypass t...

CVE-2026-40020

Attacker can use the IMAP SETACL command to inject the anyone permission to user's dovecot-acl file even if imapaclallowanyone=no. This causes folders to be spammed to all users. The impact is limited to being able to spam folders to other users, no unexpected access is gained. Install to fixed...

Net::IMAP 命令注入漏洞

Net::IMAP is a Ruby client API for the IMAP message access protocol, developed by Ruby Open Source. Versions of Net::IMAP prior to 0.4.24, 0.5.14, and 0.6.4 had command injection vulnerabilities. These vulnerabilities stemmed from the symbolic parameters of commands, which were vulnerable to CRLF...

[SECURITY] Fedora 44 Update: dovecot-2.4.3-2.fc44

Dovecot is an IMAP server for Linux/UNIX-like systems, written with security primarily in mind. It also contains a small POP3 server. It supports mail in either of maildir or mbox formats. The SQL drivers and authentication plug-ins are in their subpackages...

net-imap vulnerable to STARTTLS stripping via invalid response timing

Summary A man-in-the-middle attacker can cause Net::IMAPstarttls to return "successfully", without starting TLS. Details When using Net::IMAPstarttls to upgrade a plaintext connection to use TLS, a man-in-the-middle attacker can inject a tagged OK response with an easily predictable tag. By sendi...