ESB-2017.2346.2 - UPDATE [Win][UNIX/Linux] Ruby WEBrick: Execute arbitrary code/commands - Remote with user interaction 2017-09-18

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             AUSCERT External Security Bulletin Redistribution

        CVE-2017-10784: Escape sequence injection vulnerability in
                    the Basic authentication of WEBrick
                             18 September 2017


        AusCERT Security Bulletin Summary

Product:           Ruby WEBrick
Publisher:         Ruby
Operating System:  Windows
                   UNIX variants (UNIX, Linux, OSX)
Impact/Access:     Execute Arbitrary Code/Commands -- Remote with User Interaction
Resolution:        Patch/Upgrade
CVE Names:         CVE-2017-10784  

Original Bulletin:

Revision History:  September 18 2017: Corrected product name.
                   September 15 2017: Initial Release

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CVE-2017-10784: Escape sequence injection vulnerability in the Basic 
authentication of WEBrick

Posted by usa on 14 Sep 2017

There is an escape sequence injection vulnerability in the Basic 
authentication of WEBrick bundled by Ruby. This vulnerability has been 
assigned the CVE identifier CVE-2017-10784.


When using the Basic authentication of WEBrick, clients can pass an arbitrary
string as the user name. WEBrick outputs the passed user name intact to its 
log, then an attacker can inject malicious escape sequences to the log and 
dangerous control characters may be executed on a victims terminal emulator.

This vulnerability is similar to a vulnerability already fixed, but it had not
been fixed in the Basic authentication.

All users running an affected release should upgrade immediately.

Affected Versions

Ruby 2.2 series: 2.2.7 and earlier

Ruby 2.3 series: 2.3.4 and earlier

Ruby 2.4 series: 2.4.1 and earlier

prior to trunk revision 58453


Thanks to Yusuke Endoh for reporting this issue.


Originally published at 2017-09-14 12:00:00 (UTC)

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