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Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')


Severity High
Score 9.6/10


The package discordrb is an implementation of the Discord API using Ruby. In discordrb prior to 3.5.0 the `encoder.rb` file unsafely constructs a shell string using the file parameter, which can potentially leave clients of discordrb vulnerable to command injection. The library is not directly exploitable: the exploit requires that some client of the library calls the vulnerable method with user input. However, if unsafe input reaches the library method, then an attacker can execute arbitrary shell commands on the host machine. The full impact will depend on the permissions of the process running the `discordrb` library and will likely not be total system access. This issue has been addressed in code, but a new release of the `discordrb` gem has not been uploaded to rubygems.

  • LOW
  • HIGH
  • NONE
  • HIGH
  • HIGH

CWE-78 - OS Command Injection

The OS command injection weakness (also known as shell injection) is a vulnerability which enables an attacker to run arbitrary OS commands on a server. This is done by modifying the intended downstream OS command and injecting arbitrary commands, enabling the execution of unauthorized OS commands. This has the potential to fully compromise the application along with all of its data, and, if the compromised process does not follow the principle of least privileges, it may compromise other parts of the hosting infrastructure as well. This weakness is listed as number ten in the 'CWE Top 25 Most Dangerous Software Weaknesses'.

Advisory Timeline

  • Published