Red Hat Product Errata RHSA-2026:33540 - Security Advisory Issued: 2026-06-30 Updated: 2026-06-30 RHSA-2026:33540 - Security Advisory Overview Updated Packages Synopsis Important: ruby4.0 security update Type/Severity Security Advisory: Important Red Hat Lightspeed patch analysis Identify and remediate systems affected by this advisory. View affected systems Topic An update for ruby4.0 is now available for Red Hat Enterprise Linux 10. 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 each vulnerability from the CVE link(s) in the References section. Description Ruby is the interpreted scripting language for quick and easy object-oriented programming. It has many features to process text files and to do system management tasks (as in Perl). It is simple, straight-forward, and extensible. Security Fix(es): 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 Arguments (CVE-2026-42258) net-imap: ruby: Net::IMAP: Information disclosure via man-in-the-middle attack bypassing TLS (CVE-2026-42246) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section. Solution For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 Affected Products Red Hat Enterprise Linux for x86_64 10 x86_64 Red Hat Enterprise Linux for x86_64 - Extended Update Support 10.2 x86_64 Red Hat Enterprise Linux for IBM z Systems 10 s390x Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 10.2 s390x Red Hat Enterprise Linux for Power, little endian 10 ppc64le Red Hat Enterprise Linux for Power, little endian - Extended Update Support 10.2 ppc64le Red Hat Enterprise Linux for ARM 64 10 aarch64 Red Hat Enterprise Linux for ARM 64 - Extended Update Support 10.2 aarch64 Red Hat CodeReady Linux Builder for x86_64 10 x86_64 Red Hat CodeReady Linux Builder for Power, little endian 10 ppc64le Red Hat CodeReady Linux Builder for ARM 64 10 aarch64 Red Hat CodeReady Linux Builder for IBM z Systems 10 s390x Red Hat CodeReady Linux Builder for x86_64 - Extended Update Support 10.2 x86_64 Red Hat CodeReady Linux Builder for Power, little endian - Extended Update Support 10.2 ppc64le Red Hat CodeReady Linux Builder for IBM z Systems - Extended Update Support 10.2 s390x Red Hat CodeReady Linux Builder for ARM 64 - Extended Update Support 10.2 aarch64 Red Hat Enterprise Linux for ARM 64 - 4 years of updates 10.2 aarch64 Red Hat Enterprise Linux for IBM z Systems - 4 years of updates 10.2 s390x Red Hat Enterprise Linux for Power, little endian - 4 years of support 10.2 ppc64le Red Hat Enterprise Linux for x86_64 - 4 years of updates 10.2 x86_64 Red Hat Enterprise Linux for x86_64 - Extended Life Cycle 10.2 x86_64 Red Hat Enterprise Linux for ARM 64 - Extended Life Cycle 10.2 aarch64 Red Hat Enterprise Linux for Power, little endian - Extended Life Cycle 10.2 ppc64le Red Hat Enterprise Linux for IBM z Systems - Extended Life Cycle 10.2 s390x Fixes BZ - 2468495 - CVE-2026-42245 ruby: net-imap: Net::IMAP: Denial of Service via crafted IMAP responses BZ - 2468498 - CVE-2026-42258 ruby/net-imap: ruby: Net::IMAP: IMAP Command Injection via Symbol Arguments BZ - 2468499 - CVE-2026-42246 net-imap: ruby: Net::IMAP: Information disclosure via man-in-the-middle attack bypassing TLS CVEs CVE-2026-42245 CVE-2026-42246 CVE-2026-42258 References https://access.redhat.com/security/updates/classification/#important Note: More recent versions of these packages may be available. Click a package name for more details. Red Hat Enterprise Linux for x86_64 10 SRPM ruby4.0-4.0.3-35.el10_2.src.rpm SHA-256: 4767c6ce8a6f181a1a8e2fcd703f54a3d260a1ea3047d733e29985f313f5b3bd x86_64 ruby4.0-4.0.3-35.el10_2.x86_64.rpm SHA-256: cb511778606f8e9cc725517a0d1e06ccfc31a5f10f4c9668d72d89c2c2ee60e1 ruby4.0-debuginfo-4.0.3-35.el10_2.x86_64.rpm SHA-256: 2aa5e8f5f4ec2fc8d705ed8592850cf733fdad346e0f2c92d49cba53f974b443 ruby4.0-debugsource-4.0.3-35.el10_2.x86_64.rpm SHA-256: d81a039b5534c6934e866ec9452be767982ce38da0858f32e80d3fba7b10fb5d ruby4.0-devel-4.0.3-35.el10_2.x86_64.rpm SHA-256: 6a83babb085f0c542b5b62f94f2b98448313e6f74eb5319f5ae6d541d20ad16c ruby4.0-rubygem-mysql2-0.5.7-35.el10_2.x86_64.rpm SHA-256: ebe307e2c90c0c40ea5505cd2ebc6cd62d604e18f028d9a5563ba348019c7937 ruby4.0-rubygem-mysql2-debuginfo-0.5.7-35.el10_2.x86_64.rpm SHA-256: 1e379c54e1409bbe8d0d40a54fe27f6c4a851c42dd6a55a7f42dc47e4fc8f318 ruby4.0-rubygem-pg-1.6.3-35.el10_2.x86_64.rpm SHA-256: 5233ae3bcf375b7300128731a364be618253a96782f1fe33d654835ab1f44bd2 ruby4.0-rubygem-pg-debuginfo-1.6.3-35.el10_2.x86_64.rpm SHA-256: a1a436bb848b6489e4ae14875b8f19cf67ce7fcf3adc8754a1642ded439ada67 Red Hat Enterprise Linux for x86_64 - Extended Update Support 10.2 SRPM ruby4.0-4.0.3-35.el10_2.src.rpm SHA-256: 4767c6ce8a6f181a1a8e2fcd703f54a3d260a1ea3047d733e29985f313f5b3bd x86_64 ruby4.0-4.0.3-35.el10_2.x86_64.rpm SHA-256: cb511778606f8e9cc725517a0d1e06ccfc31a5f10f4c9668d72d89c2c2ee60e1 ruby4.0-debuginfo-4.0.3-35.el10_2.x86_64.rpm SHA-256: 2aa5e8f5f4ec2fc8d705ed8592850cf733fdad346e0f2c92d49cba53f974b443 ruby4.0-debugsource-4.0.3-35.el10_2.x86_64.rpm SHA-256: d81a039b5534c6934e866ec9452be767982ce38da0858f32e80d3fba7b10fb5d ruby4.0-devel-4.0.3-35.el10_2.x86_64.rpm SHA-256: 6a83babb085f0c542b5b62f94f2b98448313e6f74eb5319f5ae6d541d20ad16c ruby4.0-rubygem-mysql2-0.5.7-35.el10_2.x86_64.rpm SHA-256: ebe307e2c90c0c40ea5505cd2ebc6cd62d604e18f028d9a5563ba348019c7937 ruby4.0-rubygem-mysql2-debuginfo-0.5.7-35.el10_2.x86_64.rpm SHA-256: 1e379c54e1409bbe8d0d40a54fe27f6c4a851c42dd6a55a7f42dc47e4fc8f318 ruby4.0-rubygem-pg-1.6.3-35.el10_2.x86_64.rpm SHA-256: 5233ae3bcf375b7300128731a364be618253a96782f1fe33d654835ab1f44bd2 ruby4.0-rubygem-pg-debuginfo-1.6.3-35.el10_2.x86_64.rpm SHA-256: a1a436bb848b6489e4ae14875b8f19cf67ce7fcf3adc8754a1642ded439ada67 Red Hat Enterprise Linux for IBM z Systems 10 SRPM ruby4.0-4.0.3-35.el10_2.src.rpm SHA-256: 4767c6ce8a6f181a1a8e2fcd703f54a3d260a1ea3047d733e29985f313f5b3bd s390x ruby4.0-4.0.3-35.el10_2.s390x.rpm SHA-256: 98dcf10b5a46f5f05e0227ccd429f57fdb64a712c1ffae934bd46c1e7e615ad2 ruby4.0-debuginfo-4.0.3-35.el10_2.s390x.rpm SHA-256: 2b5f1aa1e0ffb38643fda0da17538557233608cca9a048c307ad92d3aea64c73 ruby4.0-debugsource-4.0.3-35.el10_2.s390x.rpm SHA-256: da380d3c0a78588143303742ae77c051d305f8722a968fd9c156be615b4187e0 ruby4.0-devel-4.0.3-35.el10_2.s390x.rpm SHA-256: 59af95feaf14f711df944ae9fdd8087c8c4c2dab645398bbd6cc21df402e08be ruby4.0-rubygem-mysql2-0.5.7-35.el10_2.s390x.rpm SHA-256: c20432b0ab9379f7a6a24aedbb98c65c79412329bebda837efbca8193e6668d8 ruby4.0-rubygem-mysql2-debuginfo-0.5.7-35.el10_2.s390x.rpm SHA-256: d2fff21633406c2a4ea7726064ecc94cfdcdd412db56c95db237da7099ff0d82 ruby4.0-rubygem-pg-1.6.3-35.el10_2.s390x.rpm SHA-256: fdf1e944437a6fbffeeff1cf699891549b25266c895a4a6216af7f857cf21ece ruby4.0-rubygem-pg-debuginfo-1.6.3-35.el10_2.s390x.rpm SHA-256: b9169a71e9b02e7911307e4e5ddbd2a1f81cc6dfb50e03c6b232d63906d57a1b Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 10.2 SRPM ruby4.0-4.0.3-35.el10_2.src.rpm SHA-256: 4767c6ce8a6f181a1a8e2fcd703f54a3d260a1ea3047d733e29985f313f5b3bd s390x ruby4.0-4.0.3-35.el10_2.s390x.rpm SHA-256: 98dcf10b5a46f5f05e0227ccd429f57fdb64a712c1ffae934bd46c1e7e615ad2 ruby4.0-debuginfo-4.0.3-35.el10_2.s390x.rpm SHA-256: 2b5f1aa1e0ffb38643fda0da17538557233608cca9a048c307ad92d3aea64c73 ruby4.0-debugsource-4.0.3-35.el10_2.s390x.rpm SHA-256: da380d3c0a78588143303742ae77c051d305f8722a968fd9c156be615b4187e0 ruby4.0-devel-4.0.3-35.el10_2.s390x.rpm SHA-256: 59af95feaf14f711df944ae9fdd8087c8c4c2dab645398bbd6cc21df402e08be ruby4.0-rubygem-mysql2-0.5.7-35.el10_2.s390x.rpm SHA-256: c20432b0ab9379f7a6a24aedbb98c65c79412329bebda837efbca8193e6668d8 ruby4.0-rubygem-mysql2-debuginfo-0.5.7-35.el10_2.s390x.rpm SHA-256: d2fff21633406c2a4ea7726064ecc94cfdcdd412db56c95db237da7099ff0d82 ruby4.0-rubygem-pg-1.6.3-35.el10_2.s390x.rpm SHA-256: fdf1e944437a6fbffeeff1cf699891549b25266c895a4a6216af7f857cf21ece ruby4.0-rubygem-pg-debuginfo-1.6.3-35.el10_2.s390x.rpm SHA-256: b9169a71e9b02e7911307e4e5ddbd2a1f81cc6dfb50e03c6b232d63906d57a1b Red Hat Enterprise Linux for Power, little endian 10 SRPM ruby4.0-4.0.3-35.el10_2.src.rpm SHA-256: 4767c6ce8a6f181a1a8e2fcd703f54a3d260a1ea3047d733e29985f313f5b3bd ppc64le ruby4.0-4.0.3-35.el10_2.ppc64le.rpm SHA-256: c05339ec953073cc15285eca55efbb6e94695c48c87b4da09cb1c4f7629383bd ruby4.0-debuginfo-4.0.3-35.el10_2.ppc64le.rpm SHA-256: 7eda42967bd64f0a88482523aaf7c2ec21b771c2e0b32fd58b4d248d54066740 ruby4.0-debugsource-4.0.3-35.el10_2.ppc64le.rpm SHA-256: 80544e3f6a439e9767103e4335a6fdede54a0a7f6fc3c036227c8acf5393b37c ruby4.0-devel-4.0.3-35.el10_2.ppc64le.rpm SHA-256: 69cb786fd64716bc3424e4201aa18ac62d9b17c4b6808efeda7889a4fdaeb3d0 ruby4.0-rubygem-mysql2-0.5.7-35.el10_2.ppc64le.rpm SHA-256: 8430ea10ca9d8a68e18df3359b1756dd8ed70fbe02257c5b50d6a3e47ddd8e39 ruby4.0-rubygem-mysql2-debuginfo-0.5.7-35.el10_2.ppc64le.rpm SHA-256: 11862a6e78d7f9ef434578149810ed488af6b0afbe5ef76d25c9268c383f3231 ruby4.0-rubygem-pg-1.6.3-35.el10_2.ppc64le.rpm SHA-256: ff4ecab7ac0835604bdf882239996dfa6495afed9bc40d7cc501334b2156651e ruby4.0-rubygem-pg-debuginfo-1.6.3-35.el10_2.ppc64le.rpm SHA-256: cd7e021d707cb0f521958b2eb8ae7308ffc9bbe4f3436475040fcc160feb1534 Red Hat Enterprise Linux for Power, little endian - Extended Update Support 10.2 SRPM ruby4.0-4.0.3-35.el10_2.src.rpm SHA-256: 4767c6ce8a6f181a1a8e2fcd703f54a3d260a1ea3047d733e29985f313f5b3bd ppc64le ruby4.0-4.0.3-35.el10_2.ppc64le.rpm SHA-256: c05339ec953073cc15285eca55efbb6e94695c48c87b4da09cb1c4f7629383bd ruby4.0-debuginfo-4.0.3-35.el10_2.ppc64le.rpm SHA-256: 7eda42967bd64f0a88