CVE-2019-5477 Information

Description

A command injection vulnerability in Nokogiri v1.10.3 and earlier allows commands to be executed in a subprocess via Ruby’s Kernel.open method. Processes are vulnerable only if the undocumented method Nokogiri::CSS::Tokenizerload_file is being called with unsafe user input as the filename. This vulnerability appears in code generated by the Rexical gem versions v1.0.6 and earlier. Rexical is used by Nokogiri to generate lexical scanner code for parsing CSS queries. The underlying vulnerability was addressed in Rexical v1.0.7 and Nokogiri upgraded to this version of Rexical in Nokogiri v1.10.4.

CVSS Vector

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

Reference

https://github.com/sparklemotion/nokogiri/issues/1915 https://github.com/tenderlove/rexical/blob/master/CHANGELOG.rdoc https://hackerone.com/reports/650835 https://lists.debian.org/debian-lts-announce/2019/09/msg00027.html https://security.gentoo.org/glsa/202006-05 https://usn.ubuntu.com/4175-1/

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

HIGH

Base Score

HIGH

Base Severity

9.8