CVE-2026-42257

CVE

Threat entity extracted from intelligence sources

Frequency

occurrences

First Seen

June 15, 2026

Last Seen

June 16, 2026

API

Exploited in Wild

—

Ransomware Use

—

Public Exploits

—

Attack Vector

—

Vulnerability Overview

Exploitation Activity

Exploitation Intelligence

Ruby IMAP Library Vulnerabilities Expose Users to MITM Attacks72.5

Two critical vulnerabilities were discovered in Ruby's Net::IMAP library affecting Ubuntu 18.04 and 16.04 LTS. CVE-2026-42246 allows remote attackers to perform machine-in-the-middle attacks by bypassing TLS encryption. CVE-2026-42257 enables attackers to inject arbitrary IMAP commands due to improp...