{"cve":"CVE-2020-8264","nvd":{"published":"2021-01-06T21:15:14.363","modified":"2026-06-17T03:26:09.527","status":"Modified","description":"In actionpack gem >= 6.0.0, a possible XSS vulnerability exists when an application is running in development mode allowing an attacker to send or embed (in another page) a specially crafted URL which can allow the attacker to execute JavaScript in the context of the local application. This vulnerability is in the Actionable Exceptions middleware.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","score":6.1},"cwes":["CWE-79"],"references":["https://groups.google.com/g/rubyonrails-security/c/yQzUVfv42jk/m/oJWw-xhNAQAJ","https://hackerone.com/reports/904059","https://groups.google.com/g/rubyonrails-security/c/yQzUVfv42jk/m/oJWw-xhNAQAJ","https://hackerone.com/reports/904059"],"products":["rubyonrails:rails"],"source":"nvd","synced_at":"2026-10-19T21:12:09.559580076+00:00"},"epss":{"cve":"CVE-2020-8264","score":0.66986,"percentile":0.99296,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-35mm-cc6r-8fjp","url":"https://osv.dev/vulnerability/GHSA-35mm-cc6r-8fjp","summary":"Cross-site scripting in actionpack","modified":"2024-02-16T07:59:11.354962Z","packages":[{"ecosystem":"RubyGems","name":"actionpack","purl":"pkg:gem/actionpack","ranges":[">=6.0.0 <6.0.3.4"],"fixed":["6.0.3.4"]}]}],"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."]}