Microsoft Security Advisory (961509): Research proves feasibility of collision attacks against MD5 - 12/30/2008
Revision Note: Advisory published Advisory Summary:Microsoft is aware that research was published at a security conference proving a successful attack against X.509 digital certificates signed using the MD5 hashing algorithm. This attack method would allow an attacker to generate additional digital certificates with different content that have the same digital signature as an original certificate. The MD5 algorithm had previously shown a vulnerability, but a practical attack had not yet been demonstrated.
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Microsoft Security Advisory (961509): Research proves feasibility of collision attacks against MD5 - 12/30/2008