{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "cpe": "cpe:2.3:a:premailer:css_parser:2.2.0:*:*:*:*:ruby:*:*",
            "extracted_events": [
              {
                "introduced": "2.2.0"
              },
              {
                "last_affected": "2.2.0"
              }
            ],
            "source": [
              "CPE_STRING",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "cee10f16b11dd175f17b0e5f6aefa488378e964b"
            },
            {
              "fixed": "7d2ddf0189cd54b54f378f59daefa10cb036e476"
            },
            {
              "fixed": "e0a151458b2a801ae265ba420862ef8b1127b3ae"
            },
            {
              "fixed": "f02be347d3a49d56ef706f5bf68621f20e3a7d40"
            }
          ],
          "repo": "https://github.com/premailer/css_parser",
          "type": "GIT"
        }
      ],
      "versions": [
        "2.2.0"
      ]
    }
  ],
  "aliases": [
    "GHSA-9pmc-p236-855h"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-918"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53727.json"
  },
  "details": "css_parser is a Ruby CSS parser. From 2.2.0 until 3.0.0, CssParser::Parser#read_remote_file in lib/css_parser/parser.rb, and therefore load_uri! and the @import-following branch of add_block!, issued HTTP and HTTPS requests against any host, port, and URI without a scheme allowlist, host or IP filtering, or protection against link-local, loopback, or RFC-1918 addresses. Location: redirects were followed recursively back into the same function, which also serviced file:// URIs, so a single attacker-controlled HTTP redirect could upgrade the bug from SSRF to arbitrary local file disclosure. Any consumer of css_parser that hands it attacker-influenced CSS together with a base_uri: option is exposed. This issue is fixed in version 3.0.0.",
  "id": "CVE-2026-53727",
  "modified": "2026-08-20T03:30:10.213343098Z",
  "published": "2026-07-17T20:30:37.291Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/premailer/css_parser/releases/tag/v3.0.0"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53727.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/premailer/css_parser/security/advisories/GHSA-9pmc-p236-855h"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-53727"
    },
    {
      "type": "FIX",
      "url": "https://github.com/premailer/css_parser/commit/7d2ddf0189cd54b54f378f59daefa10cb036e476"
    },
    {
      "type": "FIX",
      "url": "https://github.com/premailer/css_parser/commit/e0a151458b2a801ae265ba420862ef8b1127b3ae"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "css_parser: SSRF and Local File Disclosure in `CssParser::Parser#read_remote_file`"
}