ESB-2017.2347 - [Win][UNIX/Linux] Ruby: Denial of service - Existing account 2017-09-15

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             AUSCERT External Security Bulletin Redistribution

      CVE-2017-0898: Buffer underrun vulnerability in Kernel.sprintf
                             15 September 2017


        AusCERT Security Bulletin Summary

Product:           Ruby
Publisher:         Ruby
Operating System:  Windows
                   UNIX variants (UNIX, Linux, OSX)
Impact/Access:     Denial of Service        -- Existing Account
                   Access Confidential Data -- Existing Account
Resolution:        Patch/Upgrade
CVE Names:         CVE-2017-0898  

Original Bulletin:

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CVE-2017-0898: Buffer underrun vulnerability in Kernel.sprintf

Posted by usa on 14 Sep 2017

There is a buffer underrun vulnerability in the sprintf method of Kernel 
module. This vulnerability has been assigned the CVE identifier CVE-2017-0898.


If a malicious format string which contains a precious specifier (*) is passed
and a huge minus value is also passed to the specifier, buffer underrun may be
caused. In such situation, the result may contains heap, or the Ruby 
interpreter may crash.

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 aerodudrizzt for reporting this issue.


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

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