RLSA-2026:50728 (CVE-2026-27820)

Vulnerability from osv_rocky – Published: 2026-08-27 00:01 – Updated: 2026-09-10 00:12 – Source website
VLAI
Summary
Important: ruby:3.3 security, bug fix, and enhancement update
Details

Ruby is an extensible, interpreted, object-oriented, scripting language. It has features to process text files and to perform system management tasks.

Security Fix(es):

  • zlib: zlib: Memory corruption via buffer overflow in Zlib::GzipReader (CVE-2026-27820)

  • net-imap: Net::IMAP: Arbitrary IMAP command injection via CRLF sequences in unvalidated input (CVE-2026-42257)

  • ruby/net-imap: ruby: Net::IMAP: Denial of Service via large iteration count in SCRAM authentication (CVE-2026-42256)

  • net-imap: Net::IMAP: Command injection via non-synchronizing literals (CVE-2026-47240)

  • net-imap: Net::IMAP: Arbitrary IMAP command injection due to improper input validation (CVE-2026-47242)

  • net-imap: rubygem-net-imap: Net::IMAP: Denial of Service via malformed command input (CVE-2026-47241)

Bug Fix(es) and Enhancement(s):

  • ruby:3.3/ruby: Rebase to the latest Ruby 3.3 release [rhel-8] (JIRA:Rocky Linux-170929)

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.

Severity
7.3 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N
Credits
Rocky Enterprise Software Foundation
Red Hat
References
To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "Rocky Linux:8",
        "name": "ruby",
        "purl": "pkg:rpm/rocky-linux/ruby?distro=rocky-linux-8\u0026epoch=0"
      },
      "ranges": [
        {
          "database_specific": {
            "yum_repository": "AppStream"
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0:3.3.12-8.module+el8.10.0+40269+dc93e2d1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Rocky Linux:8",
        "name": "rubygem-abrt",
        "purl": "pkg:rpm/rocky-linux/rubygem-abrt?distro=rocky-linux-8\u0026epoch=0"
      },
      "ranges": [
        {
          "database_specific": {
            "yum_repository": "AppStream"
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0:0.4.0-1.module+el8.10.0+1679+61871737"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Rocky Linux:8",
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        "purl": "pkg:rpm/rocky-linux/rubygem-abrt?distro=rocky-linux-8\u0026epoch=0"
      },
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          "type": "ECOSYSTEM"
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      ]
    },
    {
      "package": {
        "ecosystem": "Rocky Linux:8",
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          "type": "ECOSYSTEM"
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    },
    {
      "package": {
        "ecosystem": "Rocky Linux:8",
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        "purl": "pkg:rpm/rocky-linux/rubygem-abrt?distro=rocky-linux-8\u0026epoch=0"
      },
      "ranges": [
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    },
    {
      "package": {
        "ecosystem": "Rocky Linux:8",
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        "purl": "pkg:rpm/rocky-linux/rubygem-abrt?distro=rocky-linux-8\u0026epoch=0"
      },
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          "type": "ECOSYSTEM"
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      ]
    },
    {
      "package": {
        "ecosystem": "Rocky Linux:8",
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        "purl": "pkg:rpm/rocky-linux/rubygem-abrt?distro=rocky-linux-8\u0026epoch=0"
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    {
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        "ecosystem": "Rocky Linux:8",
        "name": "rubygem-abrt",
        "purl": "pkg:rpm/rocky-linux/rubygem-abrt?distro=rocky-linux-8\u0026epoch=0"
      },
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            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Rocky Linux:8",
        "name": "rubygem-mysql2",
        "purl": "pkg:rpm/rocky-linux/rubygem-mysql2?distro=rocky-linux-8\u0026epoch=0"
      },
      "ranges": [
        {
          "database_specific": {
            "yum_repository": "AppStream"
          },
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          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Rocky Linux:8",
        "name": "rubygem-mysql2",
        "purl": "pkg:rpm/rocky-linux/rubygem-mysql2?distro=rocky-linux-8\u0026epoch=0"
      },
      "ranges": [
        {
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          "type": "ECOSYSTEM"
        }
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    },
    {
      "package": {
        "ecosystem": "Rocky Linux:8",
        "name": "rubygem-pg",
        "purl": "pkg:rpm/rocky-linux/rubygem-pg?distro=rocky-linux-8\u0026epoch=0"
      },
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          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Rocky Linux:8",
        "name": "rubygem-pg",
        "purl": "pkg:rpm/rocky-linux/rubygem-pg?distro=rocky-linux-8\u0026epoch=0"
      },
      "ranges": [
        {
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            "yum_repository": "AppStream"
          },
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            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "credits": [
    {
      "name": "Rocky Enterprise Software Foundation"
    },
    {
      "name": "Red Hat"
    }
  ],
  "database_specific": {
    "license": "CC-BY-4.0",
    "license_url": "https://creativecommons.org/licenses/by/4.0/",
    "source_advisory": "RHSA-2026:50728"
  },
  "details": "Ruby is an extensible, interpreted, object-oriented, scripting language. It has features to process text files and to perform system management tasks.\n\nSecurity Fix(es):\n\n* zlib: zlib: Memory corruption via buffer overflow in Zlib::GzipReader (CVE-2026-27820)\n\n* net-imap: Net::IMAP: Arbitrary IMAP command injection via CRLF sequences in unvalidated input (CVE-2026-42257)\n\n* ruby/net-imap: ruby: Net::IMAP: Denial of Service via large iteration count in SCRAM authentication (CVE-2026-42256)\n\n* net-imap: Net::IMAP: Command injection via non-synchronizing literals (CVE-2026-47240)\n\n* net-imap: Net::IMAP: Arbitrary IMAP command injection due to improper input validation (CVE-2026-47242)\n\n* net-imap: rubygem-net-imap: Net::IMAP: Denial of Service via malformed command input (CVE-2026-47241)\n\nBug Fix(es) and Enhancement(s):\n\n* ruby:3.3/ruby: Rebase to the latest Ruby 3.3 release [rhel-8] (JIRA:Rocky Linux-170929)\n\nFor 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.",
  "id": "RLSA-2026:50728",
  "modified": "2026-09-10T00:12:46.210577Z",
  "published": "2026-08-27T00:01:25.860139Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://errata.rockylinux.org/RLSA-2026:50728"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2459002"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2468494"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2468500"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2491519"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2491522"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2491523"
    },
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/errata/RHSA-2026:50728"
    }
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Important: ruby:3.3 security, bug fix, and enhancement update",
  "upstream": [
    "CVE-2026-27820",
    "CVE-2026-42256",
    "CVE-2026-42257",
    "CVE-2026-47240",
    "CVE-2026-47241",
    "CVE-2026-47242"
  ]
}



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