CNET News reports that some copies of Sendmail are implanted with a back door that could allow access to Internet attackers:

"The source code files of Sendmail 8.12.6 were apparently modified as far back as Sept. 28, according to the advisory. The Sendmail Consortium removed file transfer protocol (FTP) access to the server on Sunday. A safe version of the file can still be downloaded via the Web."

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