CVE-2020-5217 Information

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.

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N

Reference

https://github.com/twitter/secure_headers/commit/936a160e3e9659737a9f9eafce13eea36b5c9fa3 https://github.com/twitter/secure_headers/issues/418 https://github.com/twitter/secure_headers/pull/421 https://github.com/twitter/secure_headers/security/advisories/GHSA-xq52-rv6w-397c

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

CHANGED

Integrity Impact

NONE

Availability Impact

LOW

Base Score

NONE

Base Severity

5.8