{"id":"CVE-2020-5216","aliases":["GHSA-w978-rmpf-qmwg"],"url":"https://o3.security/vulnerability/CVE-2020-5216","summary":"Limited header injection when using dynamic overrides with user input in RubyGems secure_headers","details":"In Secure Headers (RubyGem secure_headers), a directive injection vulnerability is present in versions before 3.9.0, 5.2.0, and 6.3.0. If user-supplied input was passed into append/override_content_security_policy_directives, a newline could be injected leading to limited header injection. Upon seeing a newline in the header, rails will silently create a new Content-Security-Policy header with the remaining value of the original string. It will continue to create new headers for each newline. This has been fixed in 6.3.0, 5.2.0, and 3.9.0.","published":"2020-01-23T03:15:10.683Z","modified":"2026-08-07T15:13:57.222861Z","cvss":{"score":5.8,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N"},"epss":{"score":0.01079,"percentile":0.62067,"asOf":"2026-08-23"},"cisaKev":null,"exploitsKnown":1,"affectedPackages":[{"ecosystem":"RubyGems","name":"secure_headers","fixedVersion":"6.3.0"},{"ecosystem":"RubyGems","name":"secure_headers","fixedVersion":"5.2.0"},{"ecosystem":"RubyGems","name":"secure_headers","fixedVersion":"3.9.0"}],"fix":{"url":"https://github.com/twitter/secure_headers/commit/301695706f6a70517c2a90c6ef9b32178440a2d0","label":"twitter/secure_headers@3016957"},"references":[{"type":"FIX","url":"https://github.com/twitter/secure_headers/commit/301695706f6a70517c2a90c6ef9b32178440a2d0"},{"type":"EVIDENCE","url":"https://github.com/twitter/secure_headers/security/advisories/GHSA-w978-rmpf-qmwg"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-07T15:13:57.222861Z"}}