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 Executive 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 ... View Full Bio

Comment  | 
Print  | 
More Insights
Register for Dark Reading Newsletters
White Papers
Cartoon
Current Issue
Flash Poll
Video
Slideshows
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2015-4231
Published: 2015-07-03
The Python interpreter in Cisco NX-OS 6.2(8a) on Nexus 7000 devices allows local users to bypass intended access restrictions and delete an arbitrary VDC's files by leveraging administrative privileges in one VDC, aka Bug ID CSCur08416.

CVE-2015-4232
Published: 2015-07-03
Cisco NX-OS 6.2(10) on Nexus and MDS 9000 devices allows local users to execute arbitrary OS commands by entering crafted tar parameters in the CLI, aka Bug ID CSCus44856.

CVE-2015-4234
Published: 2015-07-03
Cisco NX-OS 6.0(2) and 6.2(2) on Nexus devices has an improper OS configuration, which allows local users to obtain root access via unspecified input to the Python interpreter, aka Bug IDs CSCun02887, CSCur00115, and CSCur00127.

CVE-2015-4237
Published: 2015-07-03
The CLI parser in Cisco NX-OS 4.1(2)E1(1), 6.2(11b), 6.2(12), 7.2(0)ZZ(99.1), 7.2(0)ZZ(99.3), and 9.1(1)SV1(3.1.8) on Nexus devices allows local users to execute arbitrary OS commands via crafted characters in a filename, aka Bug IDs CSCuv08491, CSCuv08443, CSCuv08480, CSCuv08448, CSCuu99291, CSCuv0...

CVE-2015-4239
Published: 2015-07-03
Cisco Adaptive Security Appliance (ASA) Software 9.3(2.243) and 100.13(0.21) allows remote attackers to cause a denial of service (device reload) by sending crafted OSPFv2 packets on the local network, aka Bug ID CSCus84220.

Dark Reading Radio
Archived Dark Reading Radio
Marc Spitler, co-author of the Verizon DBIR will share some of the lesser-known but most intriguing tidbits from the massive report