Oracle Linux 10 : ruby4.0 (ELSA-2026-20606)

The remote Oracle Linux 10 host has packages installed that are affected by multiple vulnerabilities as referenced in the ELSA-2026-20606 advisory. - Fix Net::IMAP ResponseReader quadratic complexity vulnerability CVE-2026-42245 Includes core fix plus additional performance optimizations Resolves...

SUSE SLED15: libruby3_4-3_4 / ruby3.4 / ruby3.4-devel / ruby3.4-devel-extra / etc (SUSE-SU-2026:3090-1)

The remote SUSE Linux SLED15 / SLEDSAP15 / SLES15 / SLESSAP15 host has packages installed that are affected by multiple vulnerabilities as referenced in the SUSE-SU-2026:3090-1 advisory. This update for ruby3.4 fixes the following issues - CVE-2026-42258: Net:IMAP: Command Injection via Symbol...

Security update for ruby3.4

This update for ruby3.4 fixes the following issues CVE-2026-42258: Net:IMAP: Command Injection via Symbol Arguments bsc1268011. CVE-2026-47240: Net:IMAP: Command Injection via non-synchronizing literal in "raw" argument bsc1268337. CVE-2026-47241: Net:IMAP: Denial of Service via incomplete raw...

Oracle Linux 10 : ruby4.0 (ELSA-2026-33540)

The remote Oracle Linux 10 host has packages installed that are affected by multiple vulnerabilities as referenced in the ELSA-2026-33540 advisory. - Fix Net::IMAP ResponseReader quadratic complexity vulnerability CVE-2026-42245 Includes core fix plus additional performance optimizations Resolves...

Oracle Linux 10 : ruby (ELSA-2026-33565)

The remote Oracle Linux 10 host has packages installed that are affected by multiple vulnerabilities as referenced in the ELSA-2026-33565 advisory. - Fix DoS via crafted IMAP responses in net-imap. CVE-2026-42245 Resolves: RHEL-181687 - Fix information disclosure via MITM attack bypassing TLS in...

USN-8556-1: Ruby vulnerabilities

It was discovered that the Net::IMAP client in Ruby did not properly sanitize Symbol arguments passed to IMAP commands. A remote attacker controlling a malicious IMAP server, or able to influence command arguments, could use this to inject arbitrary IMAP commands via CRLF sequences. CVE-2026-4225...

ruby security update

3.3.10-13 - Fix DoS via crafted IMAP responses in net-imap. CVE-2026-42245 Resolves: RHEL-181687 - Fix information disclosure via MITM attack bypassing TLS in net-imap. CVE-2026-42246 Resolves: RHEL-181775 - Fix command injection via Symbol arguments in net-imap. CVE-2026-42258 Resolves: RHEL-181...

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...

net-imap: Net::IMAP: Command injection via non-synchronizing literals

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 possible when an IMAP server does not support non-synchronizing literals, leading to the...

net-imap: Net::IMAP: Arbitrary IMAP command injection via CRLF sequences in unvalidated input

A flaw was found in Net::IMAP before 0.4.24, 0.5.14, and 0.6.4. Several commands accept raw string arguments sent to the server without validation or escaping; if derived from user-controlled input, CRLF sequences allow injection of arbitrary IMAP commands...

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...

CVE-2026-47240

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 possible when an IMAP server does not support non-synchronizing literals, leading to the...

MiracleLinux 8 : ruby:3.3 (AXSA:2026-1246:01)

The remote MiracleLinux 8 host has packages installed that are affected by multiple vulnerabilities as referenced in the AXSA:2026-1246:01 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...

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...

Important: Red Hat Security Advisory: ruby security update

An update for ruby is now available for Red Hat Enterprise Linux 7 Extended Lifecycle Support. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System CVSS base score, which gives a detailed severity rating, is available for...

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: 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...

net-imap: Net::IMAP: Arbitrary IMAP command injection via CRLF sequences in unvalidated input

A flaw was found in Net::IMAP before 0.4.24, 0.5.14, and 0.6.4. Several commands accept raw string arguments sent to the server without validation or escaping; if derived from user-controlled input, CRLF sequences allow injection of arbitrary IMAP commands...

RHEL 9 : ruby:3.3 (RHSA-2026:37238)

The remote Redhat Enterprise Linux 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2026:37238 advisory. Ruby is an extensible, interpreted, object-oriented, scripting language. It has features to process text files and to perform system...

Important: ruby

Issue Overview: 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...