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Sid 1-46791

Message

SERVER-WEBAPP Ruby Net FTP library command injection attempt

Summary

This event is generated when an attacker attempts to exploit a command injection vulnerability present in the Ruby NET::FTP library.

Impact

Web Application Attack

CVE-2017-17405:

CVSS base score 8.8

CVSS impact score 5.9

CVSS exploitability score 2.8

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Detailed information

Rule checks for attempts to exploit a command injection vulnerability present in the Ruby NET::FTP library. CVE-2017-17405: Ruby before 2.4.3 allows Net::FTP command injection. Net::FTP#get, getbinaryfile, gettextfile, put, putbinaryfile, and puttextfile use Kernel#open to open a local file. If the localfile argument starts with the "|" pipe character, the command following the pipe character is executed. The default value of localfile is File.basename(remotefile), so malicious FTP servers could cause arbitrary command execution.

Affected systems

  • ruby-lang ruby 2.2.0
  • ruby-lang ruby 2.5.0

Ease of attack

CVE-2017-17405:

Access Vector

Access Complexity

Authentication

False positives

Not known

False negatives

Not known

Corrective action

Update all affected products seen here: https://www.ruby-lang.org/en/news/2017/12/14/net-ftp-command-injection-cve-2017-17405/.

Contributors

  • Cisco's Talos Intelligence Group

Additional References

  • www.ruby-lang.org/en/news/2017/12/14/net-ftp-command-injection-cve-2017-17405/