Description
css_parser is a Ruby CSS parser. Prior to 2.1.0 and 1.22.0, the CSS Parser gem does not validate HTTPS connections, allowing a Man-in-the-Middle (MITM) attacker to inject or modify CSS content when stylesheets are loaded via HTTPS. The connection is established with OpenSSL::SSL::VERIFY_NONE, meaning any HTTPS certificate—even entirely untrusted—will be accepted without validation. This vulnerability is fixed in 2.1.0 and 1.22.0.
CVSS 5.8EPSS 0.146%Risk 0.59
View source- Published
- 2026-05-14 17:16:22
- Affected versions
- <2.1.0,<1.22.0
- Type
- Package
- Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N