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Integer overflow in .NET Framework
System.DirectoryServices.Protocols.Utility class
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Yorick Koster, May 2015

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Abstract
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An integer overflow exists in the
System.DirectoryServices.Protocols.Utility class of the .NET Framework.
Triggering this issue results in an overflown integer that is used to
allocate a buffer on the heap that is too small, resulting in memory
corruption. Exploiting this issues appears to be difficult.
Consequently, Microsoft has decided to not release a security bulletin.

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Affected versions
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This issue affects .NET Framework version 4.5 and 4.6. Other versions
are not affected as this issue can only be triggered using large arrays
(> 2GB).

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Fix
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There is currently no fix available for this issue. Microsoft will not
release a security bulletin, it may be fixed in future versions of the
.NET Framework.

[...] [we] are going to pursue this as a candidate for improvement in
future versions, [...] On x86, the feasibility of an attack is mitigated
by the maximum process memory and even on amd64, prevailing
configurations preclude this from being a feasible attack.

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Details
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https://www.securify.nl/advisory/SFY20150501/integer_overflow_in__net_framework_system_directoryservices_protocols_utility_class.html