ZDI-10-215: IBM Informix Dynamic Server librpc.dll Integer Overflow Remote Code Execution Vulnerability
http://www.zerodayinitiative.com/advisories/ZDI-10-215
October 18, 2010

-- CVSS:
10, (AV:N/AC:L/Au:N/C:C/I:C/A:C)

-- Affected Vendors:
IBM

-- Affected Products:
IBM Informix

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-- Vulnerability Details:
This vulnerability allows attackers to execute arbitrary code on
vulnerable installations of IBM Informix Dynamic Server. Authentication
is not required to exploit this vulnerability.

The specific flaw exists within the RPC protocol parsing library,
librpc.dll, utilized by the ISM Portmapper service (portmap.exe) bound
by default to TCP port 36890. A lack of sanity checking on supplied
parameter sizes can result in an integer overflow and subsequent heap
buffer under allocation which can finally lead to an exploitable memory
corruption.

-- Vendor Response:
IBM states:
this issue was fixed in ISM 2.20.TC1.117

Integrated into the following versions by defect#

idsdb00146931 - 7.31.xD11
idsdb00146930 - 9.40.xC10
idsdb00146929 - 10.00.xC8
idsdb00138308 - 11.10.xC2

This was fixed before 11.50 went GA; the fix is also in 11.50.

-- Disclosure Timeline:
2007-05-22 - Vulnerability reported to vendor
2010-10-18 - Coordinated public release of advisory

-- Credit:
This vulnerability was discovered by:
    * Sebastian Apelt (sebastian.apelt@siberas.de)

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