title: Directive injection when using dynamic overrides with user input in RubyGems secure_headers
description: In Secure Headers (RubyGem secure_headers), a directive injection vulnerability is present in versions before 3.8.0, 5.1.0, and 6.2.0. 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. Depending on what major version you are using, the fixed versions are 6.2.0, 5.1.0, 3.8.0.
problem types: CWE-95 Improper Neutralization of Directives in Dynamically Evaluated Code ('Eval Injection')
affected:
{
product: secure_headers
vendor: Twitter
versions:
status: affected, version: < 3.8.0
status: affected, version: >= 5.0.0, < 5.1.0
status: affected, version: >= 6.0.0, < 6.2.0
}
metrics:
cvssV3_1: [
attackComplexity: HIGH
attackVector: NETWORK
availabilityImpact: NONE
baseScore: 4.4
baseSeverity: MEDIUM
confidentialityImpact: LOW
integrityImpact: LOW
privilegesRequired: LOW
scope: CHANGED
userInteraction: REQUIRED
vectorString: CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:N
version: 3.1
]