ubuntu-cve-2026-44312
Vulnerability from osv_ubuntu
Published
2026-05-14 17:16
Modified
2026-05-14 17:16
Summary
Details

css_parser is a Ruby CSS parser. Prior to 2.1.0 and 1.22.0, the CSS Parser gem does not validate HTTPS connections, allowing a Man-in-the-Middle (MITM) attacker to inject or modify CSS content when stylesheets are loaded via HTTPS. The connection is established with OpenSSL::SSL::VERIFY_NONE, meaning any HTTPS certificate—even entirely untrusted—will be accepted without validation. This vulnerability is fixed in 2.1.0 and 1.22.0.

Severity
5.8 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
N/A (UNKNOWN)
medium
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "ruby-css-parser",
            "binary_version": "1.3.6-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:16.04:LTS",
        "name": "ruby-css-parser",
        "purl": "pkg:deb/ubuntu/ruby-css-parser@1.3.6-1?arch=source\u0026distro=xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.3.6-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "ruby-css-parser",
            "binary_version": "1.6.0-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "ruby-css-parser",
        "purl": "pkg:deb/ubuntu/ruby-css-parser@1.6.0-1?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.3.6-1",
        "1.6.0-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "ruby-css-parser",
            "binary_version": "1.6.0-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "ruby-css-parser",
        "purl": "pkg:deb/ubuntu/ruby-css-parser@1.6.0-1?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.6.0-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "ruby-css-parser",
            "binary_version": "1.6.0-2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "ruby-css-parser",
        "purl": "pkg:deb/ubuntu/ruby-css-parser@1.6.0-2?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.6.0-1",
        "1.6.0-2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "ruby-css-parser",
            "binary_version": "1.16.0-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "ruby-css-parser",
        "purl": "pkg:deb/ubuntu/ruby-css-parser@1.16.0-1?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.6.0-2",
        "1.16.0-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "ruby-css-parser",
            "binary_version": "1.19.0-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:25.10",
        "name": "ruby-css-parser",
        "purl": "pkg:deb/ubuntu/ruby-css-parser@1.19.0-1?arch=source\u0026distro=questing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.19.0-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "ruby-css-parser",
            "binary_version": "1.21.1-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "ruby-css-parser",
        "purl": "pkg:deb/ubuntu/ruby-css-parser@1.21.1-1?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.19.0-1",
        "1.21.1-1"
      ]
    }
  ],
  "aliases": [],
  "details": "css_parser is a Ruby CSS parser. Prior to 2.1.0 and 1.22.0, the CSS Parser gem does not validate HTTPS connections, allowing a Man-in-the-Middle (MITM) attacker to inject or modify CSS content when stylesheets are loaded via HTTPS. The connection is established with OpenSSL::SSL::VERIFY_NONE, meaning any HTTPS certificate\u2014even entirely untrusted\u2014will be accepted without validation. This vulnerability is fixed in 2.1.0 and 1.22.0.",
  "id": "UBUNTU-CVE-2026-44312",
  "modified": "2026-05-14T17:16:00Z",
  "published": "2026-05-14T17:16:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-44312"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-44312"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/premailer/css_parser/security/advisories/GHSA-ff6c-w6qf-7xqc"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/premailer/css_parser/issues/185"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/premailer/css_parser/commit/35e689c904225add78e0c488cf04bad052666449"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/premailer/css_parser/commit/e0c95d5abe91b237becb90ff316531a6547ada18"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-44312"
  ]
}



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