ghsa-xq52-rv6w-397c
Vulnerability from github
Impact
If user-supplied input was passed into append/override_content_security_policy_directives, a semicolon could be injected leading to directive injection.
This 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.
The 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.
Duplicate script-src directives detected. All but the first instance will be ignored.
See https://www.w3.org/TR/CSP3/#parse-serialized-policy
Note: In this case, the user agent SHOULD notify developers that a duplicate directive was ignored. A console warning might be appropriate, for example.
Patches
Depending on what major version you are using, the fixed versions are 6.2.0, 5.1.0, 3.8.0.
Workarounds
If you are passing user input into the above methods, you could filter out the input:
ruby
override_content_security_policy_directives(:frame_src, [user_input.gsub(";", " ")])
References
Reported in https://github.com/twitter/secure_headers/issues/418 https://www.w3.org/TR/CSP3/#parse-serialized-policy
For more information
If you have any questions or comments about this advisory: * Open an issue in this repo * DM @ndm on twitter
{
"affected": [
{
"package": {
"ecosystem": "RubyGems",
"name": "secure_headers"
},
"ranges": [
{
"events": [
{
"introduced": "6.0.0"
},
{
"fixed": "6.2.0"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "RubyGems",
"name": "secure_headers"
},
"ranges": [
{
"events": [
{
"introduced": "5.0.0"
},
{
"fixed": "5.1.0"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "RubyGems",
"name": "secure_headers"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "3.8.0"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2020-5217"
],
"database_specific": {
"cwe_ids": [
"CWE-95"
],
"github_reviewed": true,
"github_reviewed_at": "2020-01-23T02:12:03Z",
"nvd_published_at": null,
"severity": "MODERATE"
},
"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\u003e 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\u003e 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 ",
"id": "GHSA-xq52-rv6w-397c",
"modified": "2023-05-16T16:09:56Z",
"published": "2020-01-23T02:28:11Z",
"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"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:N",
"type": "CVSS_V3"
}
],
"summary": "Directive injection when using dynamic overrides with user input"
}
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.