ZDNN: Major Unix flaw emerges | Linux Today

ZDNN: Major Unix flaw emerges

Written By
Web Webster
Web Webster
Mar 1, 1999

“A newly discovered Unix design flaw threatens thousands of
computers that operate on the Internet.”

“By not terminating the connection, the program quickly loaded
up his Unix server’s “process tables” and brought the ISP to a
standstill for two hours.”

“The attack entails sending repeated open-connection requests to
a Unix server. Subprograms – like Internet Daemon, Secure Shell
Daemon and Internet Message Access Protocol Daemon – are written to
automatically answer the connection and carry out requests. But if
the connection is initiated with no request, most Daemons keep the
line open, using resources from the server’s process table, which
can handle between 600 and 1,500 simultaneous tasks. Repeated
connections eventually overload the process table and crash the
server.”

Complete
Story

Web Webster

Web Webster

Web Webster has more than 20 years of writing and editorial experience in the tech sector. He’s written and edited news, demand generation, user-focused, and thought leadership content for business software solutions, consumer tech, and Linux Today, he edits and writes for a portfolio of tech industry news and analysis websites including webopedia.com, and DatabaseJournal.com.

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