css_parser allows to MITM included https css urls_CVE-2026-44312

5.8 / 10

MEDIUM

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

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.

Basic Information

ID CVE-2026-44312

Source GitHub_M

Published May 14, 2026 at 16:15

Affected Product

Vendor premailer

Product css_parser

Version >= 2.0.0, < 2.1.0

Affected Versions premailer css_parser >= 2.0.0, < 2.1.0
premailer css_parser < 1.22.0

CWE Classification

CWE-829 CWE-295

References

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    "published": "2026-05-14T16:15:04.907Z",
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    "type": "cve",
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