Nokogiri up to 1.10.3 Ruby Tokenizer#load_file Filename command injection

Summaryinfo

A vulnerability, which was classified as critical, was found in Nokogiri up to 1.10.3. The impacted element is the function Nokogiri::CSS::Tokenizer#load_file of the component Ruby. The manipulation as part of Filename results in command injection. This vulnerability was named CVE-2019-5477. The attack may be performed from remote. There is no available exploit. You should upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in Nokogiri up to 1.10.3. Affected is the function Nokogiri::CSS::Tokenizer#load_file of the component Ruby. The manipulation as part of a Filename leads to a command injection vulnerability. CWE is classifying the issue as CWE-77. The product constructs all or part of a command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended command when it is sent to a downstream component. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

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::Tokenizer#load_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.

The weakness was presented 08/16/2019 (GitHub Repository). The advisory is shared for download at github.com. This vulnerability is traded as CVE-2019-5477 since 01/04/2019. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1202.

Upgrading to version 1.10.4 eliminates this vulnerability.

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Productinfo

Name

• Nokogiri

Version

• 1.10.0
• 1.10.1
• 1.10.2
• 1.10.3

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CPE 2.2info

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