| Name | CVE-2026-44312 |
| 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. |
| Source | CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| ruby-css-parser (PTS) | bullseye | 1.6.0-1 | vulnerable |
| bookworm | 1.6.0-2 | vulnerable | |
| trixie | 1.19.0-1 | vulnerable | |
| forky, sid | 2.1.0-1 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|---|---|---|---|---|---|
| ruby-css-parser | source | (unstable) | 2.1.0-1 |
[trixie] - ruby-css-parser <no-dsa> (Minor issue)
[bookworm] - ruby-css-parser <no-dsa> (Minor issue)
[bullseye] - ruby-css-parser <postponed> (Minor issue)
https://github.com/premailer/css_parser/security/advisories/GHSA-ff6c-w6qf-7xqc
https://github.com/premailer/css_parser/issues/185
Fixed by: https://github.com/premailer/css_parser/commit/35e689c904225add78e0c488cf04bad052666449 (v2.1.0)
Fixed by: https://github.com/premailer/css_parser/commit/e0c95d5abe91b237becb90ff316531a6547ada18 (v1.22.0)