Gavin Andresen, a bitcoin.org developer has posted on bitcointalk an important Windows bitcoin-qt update message.

URGENT: Windows Bitcoin-Qt update
On March 17, 2012, 12:17:15 AM.

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A potential security vulnerability has been discovered in the Windows
version of Bitcoin-Qt. If you are running Bitcoin-Qt versions 0.5
through 0.6 on Windows you should shut it down and upgrade to either
version 0.5.3.1 or 0.6rc4 NOW.

The command-line bitcoin daemon (bitcoind), Mac and Linux versions of
Bitcoin-Qt, and versions prior to 0.5 are not affected.

Due to the nature of the vulnerability, we believe it would be very
difficult for an attacker to do anything more than crash the
Bitcoin-Qt process. However, because there is a possibility of such a
crash causing remote code execution we consider this a critical issue.

Binaries are available at SourceForge:
https://sourceforge.net/projects/bitcoin/files/Bitcoin/bitcoin-0.6.0/test/
https://sourceforge.net/projects/bitcoin/files/Bitcoin/bitcoin-0.5.3/

If you have questions, feel free to drop by the #bitcoin-dev channel
on FreeNode IRC.

- --
Gavin Andresen
Gregory Maxwell
Matt Corallo
Nils Schneider
Wladimir J. van der Laan
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