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.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
premailer css_parser
>= 2.0.0, < 2.1.0affected< 1.22.0affected
References
- https://github.com/premailer/css_parser/security/advisories/GHSA-ff6c-w6qf-7xqc ↗
- https://github.com/premailer/css_parser/issues/185 ↗
- https://github.com/premailer/css_parser/commit/35e689c904225add78e0c488cf04bad052666449 ↗
- https://github.com/premailer/css_parser/commit/e0c95d5abe91b237becb90ff316531a6547ada18 ↗