net-imap: ruby: Net::IMAP: Information disclosure via man-in-the-middle attack bypassing TLS

A flaw was found in the Ruby net-imap library. When upgrading a cleartext IMAP connection to TLS using the Net::IMAPstarttls method, the library improperly handles certain responses received during STARTTLS negotiation. A man-in-the-middle MITM attacker can inject a predicted tagged OK response...

Linux Distros Unpatched Vulnerability : CVE-2026-42246

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available. - Net::IMAP implements Internet Message Access Protocol IMAP client functionality in Ruby. Prior to versions 0.3.10, 0.4.24, 0.5.14, and 0.6.4, a man-in-the-middl...

DEBIAN-CVE-2026-42246

Net::IMAP implements Internet Message Access Protocol IMAP client functionality in Ruby. Prior to versions 0.3.10, 0.4.24, 0.5.14, and 0.6.4, a man-in-the-middle attacker can cause Net::IMAPstarttls to return "successfully", without starting TLS. This issue has been patched in versions 0.3.10,...

CVE-2026-42246

Net::IMAP implements Internet Message Access Protocol IMAP client functionality in Ruby. Prior to versions 0.3.10, 0.4.24, 0.5.14, and 0.6.4, a man-in-the-middle attacker can cause Net::IMAPstarttls to return "successfully", without starting TLS. This issue has been patched in versions 0.3.10,...

MiracleLinux 8 : fetchmail-6.4.24-1.el8.ML.1 (AXSA:2022-3362:02)

The remote MiracleLinux 8 host has a package installed that is affected by multiple vulnerabilities as referenced in the AXSA:2022-3362:02 advisory. fetchmail: DoS or information disclosure when logging long messages CVE-2021-36386 fetchmail: STARTTLS session encryption bypassing CVE-2021-39272...

USN-8478-1 ruby2.7, ruby3.0, ruby3.2, ruby3.3 vulnerabilities

It was discovered that Ruby's Net::IMAP library did not properly verify that TLS encryption was started after issuing a STARTTLS command. A remote attacker could use this to perform a machine-in-the-middle attack and silently bypass TLS encryption. CVE-2026-42246 It was discovered that Ruby's...

CVE-2021-38372

In KDE Trojita 0.7, man-in-the-middle attackers can create new folders because untagged responses from an IMAP server are accepted before STARTTLS...