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

CVE-2021-23632

Severity High
Score 9.8/10

Summary

All versions of package git are vulnerable to Remote Code Execution (RCE) due to missing sanitization in the Git.git method, which allows execution of OS commands rather than just git commands. Steps to Reproduce 1. Create a file named exploit.js with the following content: js var Git = require("git").Git; var repo = new Git("repo-test"); var user_input = "version; date"; repo.git(user_input, function(err, result) { console.log(result); }) 2. In the same directory as exploit.js, run npm install git. 3. Run exploit.js: node exploit.js. You should see the outputs of both the git version and date command-lines. Note that the repo-test Git repository does not need to be present to make this PoC work.

  • LOW
  • NETWORK
  • HIGH
  • UNCHANGED
  • NONE
  • 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