RHSA-2026:50778HighCVSS 7.3

Red Hat Security Advisory: ruby security, bug fix, and enhancement update

Published
August 5, 2026
Last Modified
August 26, 2026

🔗 CVE IDs covered (6)

CVE-2026-27820 →CVE-2026-42256 →CVE-2026-42257 →CVE-2026-47240 →CVE-2026-47241 →CVE-2026-47242 →

📋 Description

CVE-2026-27820 — zlib: zlib: Memory corruption via buffer overflow in Zlib::GzipReader CVE-2026-42256 — ruby/net-imap: ruby: Net::IMAP: Denial of Service via large iteration count in SCRAM authentication CVE-2026-42257 — net-imap: Net::IMAP: Arbitrary IMAP command injection via CRLF sequences in unvalidated input CVE-2026-47240 — net-imap: Net::IMAP: Command injection via non-synchronizing literals CVE-2026-47241 — net-imap: rubygem-net-imap: Net::IMAP: Denial of Service via malformed command input CVE-2026-47242 — net-imap: Net::IMAP: Arbitrary IMAP command injection due to improper input validation

🎯 Affected products97

  • Red Hat Enterprise Linux AppStream (v. 10)
  • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)
  • ruby-0:3.3.12-14.el10_2.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • ruby-0:3.3.12-14.el10_2.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • ruby-0:3.3.12-14.el10_2.s390x as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • ruby-0:3.3.12-14.el10_2.src as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • ruby-0:3.3.12-14.el10_2.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • ruby-bundled-gems-0:3.3.12-14.el10_2.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • ruby-bundled-gems-0:3.3.12-14.el10_2.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • ruby-bundled-gems-0:3.3.12-14.el10_2.s390x as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • ruby-bundled-gems-0:3.3.12-14.el10_2.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • ruby-bundled-gems-debuginfo-0:3.3.12-14.el10_2.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • ruby-bundled-gems-debuginfo-0:3.3.12-14.el10_2.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • ruby-bundled-gems-debuginfo-0:3.3.12-14.el10_2.s390x as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • ruby-bundled-gems-debuginfo-0:3.3.12-14.el10_2.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • ruby-debuginfo-0:3.3.12-14.el10_2.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • ruby-debuginfo-0:3.3.12-14.el10_2.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • ruby-debuginfo-0:3.3.12-14.el10_2.s390x as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • ruby-debuginfo-0:3.3.12-14.el10_2.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • ruby-debugsource-0:3.3.12-14.el10_2.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • ruby-debugsource-0:3.3.12-14.el10_2.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • ruby-debugsource-0:3.3.12-14.el10_2.s390x as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • ruby-debugsource-0:3.3.12-14.el10_2.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • ruby-default-gems-0:3.3.12-14.el10_2.noarch as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • ruby-devel-0:3.3.12-14.el10_2.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • ruby-devel-0:3.3.12-14.el10_2.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • ruby-devel-0:3.3.12-14.el10_2.s390x as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • ruby-devel-0:3.3.12-14.el10_2.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • ruby-doc-0:3.3.12-14.el10_2.noarch as a component of Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)
  • ruby-libs-0:3.3.12-14.el10_2.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • +67 more not shown

✅ Remediation

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 Workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability. Workaround: Explicitly validate user-controlled inputs to prevent embedded non-synchronizing literals unless the server supports them. For a simpler, more cautious approach: all embedded literals can be unconditionally prohibited, by checking that string inputs do not contain any CR or LF bytes. Workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability. Update to the fixed version of affected product.

🔗 References (9)