[SA21009] Ruby Safe Level Security Bypass Vulnerabilities

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Hardcore Disassembler / Reverse Engineer

Reversing must be a passion as your skills will be challenged
on a daily basis and you will be working several hours
everyday in IDA, Ollydbg, and with BinDiff. Often, it is also
required that you write a PoC or even a working exploit to
prove that an issue is exploitable.

http://secunia.com/hardcore_disassembler_and_reverse_engineer/

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TITLE:
Ruby Safe Level Security Bypass Vulnerabilities

SECUNIA ADVISORY ID:
SA21009

VERIFY ADVISORY:
http://secunia.com/advisories/21009/

CRITICAL:
Less critical

IMPACT:
Security Bypass

WHERE:
>From remote

SOFTWARE:
Ruby 1.6.x
http://secunia.com/product/5754/
Ruby 1.8.x
http://secunia.com/product/3787/

DESCRIPTION:
Two vulnerabilities have been reported in Ruby, which can be
exploited by malicious people to bypass certain security
restrictions.

1) An error in the handling of the "alias" functionality can be
exploited to bypass the safe level protection and replace methods
called in the trusted level.

2) An error caused due to directory operations not being properly
checked can be exploited to bypass the safe level protection and
close untainted directory streams.

The vulnerabilities have been reported in version 1.8.4 and prior.

SOLUTION:
The vulnerabilities have been fixed in a snapshot version and will
also be fixed in the upcoming 1.8.5 version.

PROVIDED AND/OR DISCOVERED BY:
Reported by the vendor.

ORIGINAL ADVISORY:
JP Vendor Status Notes (Japanese):
http://jvn.jp/jp/JVN%2383768862/index.html
http://jvn.jp/jp/JVN%2313947696/index.html

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About:
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