{"cve":"CVE-2026-53727","nvd":{"published":"2026-07-17T21:17:07.837","modified":"2026-10-24T20:10:00.137","status":"Analyzed","description":"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.","cvss_v4":{"vector":"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","score":8.9},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N","score":8.6},"cwes":["CWE-918"],"references":["https://github.com/premailer/css_parser/commit/7d2ddf0189cd54b54f378f59daefa10cb036e476","https://github.com/premailer/css_parser/commit/e0a151458b2a801ae265ba420862ef8b1127b3ae","https://github.com/premailer/css_parser/releases/tag/v3.0.0","https://github.com/premailer/css_parser/security/advisories/GHSA-9pmc-p236-855h","https://github.com/premailer/css_parser/security/advisories/GHSA-9pmc-p236-855h"],"products":["premailer:css_parser"],"source":"nvd","synced_at":"2026-10-25T17:50:08.599881581+00:00"},"epss":{"cve":"CVE-2026-53727","score":0.00506,"percentile":0.42935,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-9pmc-p236-855h","url":"https://osv.dev/vulnerability/GHSA-9pmc-p236-855h","summary":"Ruby CSS Parser: SSRF and Local File Disclosure in `CssParser::Parser#read_remote_file`","modified":"2026-07-09T14:11:38.811463Z","packages":[{"ecosystem":"RubyGems","name":"css_parser","purl":"pkg:gem/css_parser","ranges":["<3.0.0"],"fixed":["3.0.0"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}