CVE Vulnerabilities

CVE-2019-18409

Incorrect Permission Assignment for Critical Resource

Published: Oct 24, 2019 | Modified: Oct 30, 2019
CVSS 3.x
7.8
HIGH
Source:
NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CVSS 2.x
4.6 MEDIUM
AV:L/AC:L/Au:N/C:P/I:P/A:P
RedHat/V2
RedHat/V3
Ubuntu

The ruby_parser-legacy (aka legacy) gem 1.0.0 for Ruby allows local privilege escalation because of world-writable files. For example, if the brakeman gem (which has a legacy dependency) 4.5.0 through 4.7.0 is used, a local user can insert malicious code into the ruby_parser-legacy-1.0.0/lib/ruby_parser/legacy/ruby_parser.rb file.

Weakness

The product specifies permissions for a security-critical resource in a way that allows that resource to be read or modified by unintended actors.

Affected Software

Name Vendor Start Version End Version
Ruby_parser-legacy Zenspider 1.0.0 (including) 1.0.0 (including)

Potential Mitigations

  • Run the code in a “jail” or similar sandbox environment that enforces strict boundaries between the process and the operating system. This may effectively restrict which files can be accessed in a particular directory or which commands can be executed by the software.
  • OS-level examples include the Unix chroot jail, AppArmor, and SELinux. In general, managed code may provide some protection. For example, java.io.FilePermission in the Java SecurityManager allows the software to specify restrictions on file operations.
  • This may not be a feasible solution, and it only limits the impact to the operating system; the rest of the application may still be subject to compromise.
  • Be careful to avoid CWE-243 and other weaknesses related to jails.

References