Attacks/Breaches
12/16/2008
02:46 PM
Connect Directly
Google+
Twitter
RSS
E-Mail
50%
50%

Researcher Releases Free DoS Hacking Tool

'LetDown' can take down a Website, find DoS weaknesses

A researcher has unleashed a free denial-of-service (DoS) hacking tool for flooding TCP sessions.

Called LetDown, the penetration testing tool is part of a larger package of tools called Complemento that was created by Italian researcher Acri Emanuele. "Complemento is a collection of tools that I originally grokked up for my personal toolchain for solving some problems or just for fun," Emanuele wrote in his post announcing the availability of the tools. He also admits having concerns about releasing LetDown to the public.

"I had some doubts, because with this tool [it] is possible to crash a server configured in the wrong way using very slow connections, without the need of botnets. A great fun for script kiddies," Emanuele told Dark Reading.

"Basically, LetDown is a TCP flooder that completes the three-way handshake and sends a requests to the server without closing the connection," he said. "LetDown is aimed specifically at pen testers and server owners that want to test the resiliency of their networks against DoS attacks in order to properly configure the rules on resource management on their systems."

The other Complemento tools include a domain scanner called Reverse Raider that brute-force scans target subdomains or performs reverse-resolution for IP address ranges, and Httsquash, an HTTP server scanner, banner grabber, and data retriever. Complemento is available here for download.

A TCP "flood" attack can take down a Website, for instance. And as with any hacking tool, the danger is that LetDown could fall into the wrong hands. "This tool will have some negative impact for its victims," says Robert E. Lee, chief security officer of Outpost24.

LetDown may be useful for testing for DoS weaknesses, says Jack Lewis, a senior researcher with Outpost24, who, along with Lee, recently discovered a TCP DoS vulnerability that executes a lethal DoS attack against broadband Internet connections. "Some people want to test a network against DoS attacks. I don't think many do, but it may be useful to someone," he says. "It would be a lot more helpful, though, if there were workarounds to these problems," which there are in this case, he notes.

While security experts say it's rare for DoS hacking tools to be released these days, other similar tools have been around for some time. "'Unicornscan' can do it better," for example, Lewis says.

Have a comment on this story? Please click "Discuss" below. If you'd like to contact Dark Reading's editors directly, send us a message Kelly Jackson Higgins is Senior Editor at DarkReading.com. She is an award-winning veteran technology and business journalist with more than two decades of experience in reporting and editing for various publications, including Network Computing, Secure Enterprise Magazine, ... View Full Bio

Comment  | 
Print  | 
More Insights
Register for Dark Reading Newsletters
White Papers
Flash Poll
Current Issue
Cartoon
Video
Slideshows
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2014-2963
Published: 2014-07-10
Multiple cross-site scripting (XSS) vulnerabilities in group/control_panel/manage in Liferay Portal 6.1.2 CE GA3, 6.1.X EE, and 6.2.X EE allow remote attackers to inject arbitrary web script or HTML via the (1) _2_firstName, (2) _2_lastName, or (3) _2_middleName parameter.

CVE-2014-3310
Published: 2014-07-10
The File Transfer feature in WebEx Meetings Client in Cisco WebEx Meetings Server and WebEx Meeting Center does not verify that a requested file was an offered file, which allows remote attackers to read arbitrary files via a modified request, aka Bug IDs CSCup62442 and CSCup58463.

CVE-2014-3311
Published: 2014-07-10
Heap-based buffer overflow in the file-sharing feature in WebEx Meetings Client in Cisco WebEx Meetings Server and WebEx Meeting Center allows remote attackers to execute arbitrary code via crafted data, aka Bug IDs CSCup62463 and CSCup58467.

CVE-2014-3315
Published: 2014-07-10
Cross-site scripting (XSS) vulnerability in viewfilecontents.do in the Dialed Number Analyzer (DNA) component in Cisco Unified Communications Manager allows remote attackers to inject arbitrary web script or HTML via an unspecified parameter, aka Bug ID CSCup76308.

CVE-2014-3316
Published: 2014-07-10
The Multiple Analyzer in the Dialed Number Analyzer (DNA) component in Cisco Unified Communications Manager allows remote authenticated users to bypass intended upload restrictions via a crafted parameter, aka Bug ID CSCup76297.

Best of the Web
Dark Reading Radio
Archived Dark Reading Radio
Marilyn Cohodas and her guests look at the evolving nature of the relationship between CIO and CSO.