ESB-2017.3205 - [Win][UNIX/Linux] Ruby: Execute arbitrary code/commands - Remote with user interaction 2017-12-15

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             AUSCERT External Security Bulletin Redistribution

                   Command injection patched in Net::FTP
                             15 December 2017


        AusCERT Security Bulletin Summary

Product:           Ruby
Publisher:         Ruby
Operating System:  UNIX variants (UNIX, Linux, OSX)
Impact/Access:     Execute Arbitrary Code/Commands -- Remote with User Interaction
Resolution:        Patch/Upgrade
CVE Names:         CVE-2017-17405  

Original Bulletin:

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CVE-2017-17405: Command injection vulnerability in Net::FTP

Posted by nagachika on 14 Dec 2017

There is a command injection vulnerability in Net::FTP bundled with Ruby. This
vulnerability has been assigned the CVE identifier CVE-2017-17405.


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.

All users running an affected release should upgrade immediately.

Affected Versions

  * Ruby 2.2 series: 2.2.8 and earlier
  * Ruby 2.3 series: 2.3.5 and earlier
  * Ruby 2.4 series: 2.4.2 and earlier
  * Ruby 2.5 series: 2.5.0-preview1
  * prior to trunk revision r61242


Thanks to Etienne Stalmans from the Heroku product security team for reporting
the issue.


  * Originally published at 2017-12-14 16:00:00 (UTC)

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