CVE-2020-5217: Secure headers Directive Injection When Using Dynamic Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-xq52-rv6w-397c",
  "modified" : "2023-05-16T16:09:56Z",
  "published" : "2020-01-23T02:28:11Z",
  "aliases" : [ "CVE-2020-5217" ],
  "summary" : "Directive injection when using dynamic overrides with user input",
  "details" : "### Impact\n\nIf user-supplied input was passed into `append/override_content_security_policy_directives`, a semicolon could be injected leading to directive injection.\n\nThis could be used to e.g. override a `script-src` directive. Duplicate directives are ignored and the first one wins. The directives in `secure_headers` are sorted alphabetically so they pretty much all come before `script-src`. A previously undefined directive would receive a value even if `SecureHeaders::OPT_OUT` was supplied.\n\nThe fixed versions will silently convert the semicolons to spaces and emit a deprecation warning when this happens. This will result in innocuous browser console messages if being exploited/accidentally used. In future releases, we will raise application errors resulting in 500s.\n\n> Duplicate script-src directives detected.  All but the first instance will be ignored.\n\nSee https://www.w3.org/TR/CSP3/#parse-serialized-policy\n\n> Note: In this case, the user agent SHOULD notify developers that a duplicate directive was ignored. A console warning might be appropriate, for example.\n\n### Patches\n\nDepending on what major version you are using, the fixed versions are 6.2.0, 5.1.0, 3.8.0.\n\n### Workarounds\n\nIf you are passing user input into the above methods, you could filter out the input:\n\n```ruby\noverride_content_security_policy_directives(:frame_src, [user_input.gsub(\";\", \" \")])\n```\n\n### References\n\nReported in https://github.com/twitter/secure_headers/issues/418\nhttps://www.w3.org/TR/CSP3/#parse-serialized-policy\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/issues/new)\n* DM @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" : "6.2.0"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "RubyGems",
      "name" : "secure_headers"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "5.0.0"
      }, {
        "fixed" : "5.1.0"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "RubyGems",
      "name" : "secure_headers"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "3.8.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/twitter/secure_headers/security/advisories/GHSA-xq52-rv6w-397c"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2020-5217"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/twitter/secure_headers/issues/418"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/twitter/secure_headers/pull/421"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/twitter/secure_headers/commit/936a160e3e9659737a9f9eafce13eea36b5c9fa3"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/rubysec/ruby-advisory-db/blob/master/gems/secure_headers/CVE-2020-5217.yml"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/twitter/secure_headers"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-95" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2020-01-23T02:12:03Z",
    "nvd_published_at" : null
  }
}