The Domain Name System (DNS) translates Internet domain and host names to IP addresses.
20
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3answers
716 views
What are some risks of purchasing a “used” domain name
If you purchase an existing domain name that was already used by someone else what are the ways in which the domain could have been broken by the previous owner? Are such problems common and are there ...
18
votes
6answers
2k views
Why do DDoS attacks cost a fortune to stop?
I have read so many stories that a major DDoS attack is causing companies thousands of dollars to mitigate. I have two questions:
Is this because they try to keep the servers accessible to real site ...
15
votes
4answers
592 views
Global Blackout is a myth?
In order to shut the Internet down, anonymous claimed that putting-down the
13 root DNS servers of the Internet and therefore disabling the HTTP Internet, the most widely used function of the Web, ...
15
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3answers
918 views
DNS Amplification DDOS attack
During the weekend I made some tests to simulate an DNS Amplification DDOS attack. sending about 90Mb/s traffic I was able to generate about x.x Gb/s amplified traffic which sent our datacenter ...
14
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7answers
952 views
Would it be possible to overload a large part of the internet, and if so then how?
Last week a news article went viral about a Dutch web hosting/data center company that was allegedly using a DNS amplification attack to DDoS an anti-spam company, because they blacklisting the ...
13
votes
5answers
4k views
Do you detect/react to DNS tunnelling?
I've just seen a talk about tunnelling TCP/IP over DNS requests, because port 53 UDP is usually open and unfiltered. What techniques exist to detect and block such tunnels, and have you ever seen that ...
12
votes
4answers
2k views
Does TOR Hidden Service Protocol provide more threat protection than a standard HTTPS session?
DuckDuckGo is a search engine that has a TOR Exit Enclave. This site is focused on the safe, secure searching of its users.
Since DNS is not used in TOR, it appears that HTTPS is less secure due to ...
10
votes
7answers
783 views
Can a HTTPS connection be compromised because of a rogue DNS server
If I'm visiting (just a desktop pc, client side) a site that has a valid HTTPS cert/connection, that can it be compromised if I'm using [not with free will, so e.g.: I'm "attacked"] a rouge DNS ...
8
votes
4answers
1k views
Is NTP vulnerable to DNS poisoning or spoofing attacks?
Scenario:
Attacker somehow compromises the DNS lookup for the NTP server used by the victim (a web application)
Victim sends DNS request for e.g. ntp.pool.org, which is responded to by attacker to ...
8
votes
2answers
200 views
Do any DNS registrars support multi factor authentication?
I am looking for a DNS registrar that supports strong multi-factor authentication.
Does any DNS registrar support multi-factor?
Is this a legitimate need?
6
votes
2answers
3k views
DNS zone transfer attack
Hello Guys! Can anyone explain what is DNS zone transfer or give any link, paper? I have already googled, but could not find anything meaningful?
6
votes
2answers
1k views
Initial steps of network mapping
In light of recent security breaches hitting the news, it's been all hands on deck at my work as far as security. I'm trying to pen test our network. I have a very basic question.
My Question
You ...
6
votes
3answers
1k views
What's involved in taking over someone else's domain name?
I'm asking this for purely academic reasons.
I know that there are domain record lists and whatnot, but I'm trying to understand the exact structure of how DNS works and where someone can potentially ...
6
votes
3answers
344 views
Is the Kaminsky bug still a problem for sites without DNSSEC?
I have read about the Kaminsky bug, but I don't fully understand how easy it is to use this vulnerability for an attacker.
Are DNS-software updated now so it's not that easy to use this vulnerability ...
6
votes
1answer
1k views
How to create your own RBL DNS Blacklist to prevent spam
I am getting sick of reporting the same old chinese emails to Spamcop now and would like to make my own small RBL list that I can easily add blocks of IP's to.
I have a spare PC and static IP address ...
5
votes
2answers
3k views
How can I detect/withstand DNS amplification attack?
I am a developer, and I am trying to get an insight into what could I do to enable my application to withstand a DNS amplification kind of attacks. Would such prevention methods help against DOS type ...
5
votes
2answers
2k views
How can I identify open DNS resolvers in my network?
This article highlights how open DNS resolvers are being used to create DDOS attacks across the internet. How can I identify whether any of our DNS servers are open? If I find that we are running ...
5
votes
2answers
466 views
Could somebody explain how DNS poisoning might occur in this scenario?
I read the following statement in a security blog
using the same source port over and over again for dns queries instead of randomizing them is a vulnerability for dns poisoning
Could somebody ...
5
votes
3answers
169 views
Why would you want to run DNS servers externally?
Something that's never made much sense to me is when environments have DNS servers which are publicly accessible (on the internet). This more often than not seems to leave them vulnerable to Cache ...
5
votes
3answers
269 views
Does NAT break source port randomization?
The standard defense against the Kaminsky attack is to use source port randomization for all DNS requests.
Does NAT break the security benefits of source port randomization?
In more detail, consider ...
5
votes
2answers
965 views
How bad is the leaking of Internal IP addresses through external DNS
If an external DNS server is leaking internal IP addresses are there any significant security threats associated with this information leakage?
Apart from most the obvious - gaining an understanding ...
5
votes
2answers
316 views
Is this a DNS attack?
The following graph shows the UDP DNS queries/sec (blue) and DNS responses/sec (red) of traffic passing a router over the preiod of 4 days. DNS query is a DNS packet with query/response flag set to 0 ...
5
votes
1answer
645 views
Implications of using DNS Forwarders instead of Root Hints
When redesigning an organizations DNS infrastructure, the question of using Forwarders instead of Root Hints comes up. What kinds of issues should I be aware of when the admins and designers start ...
4
votes
6answers
10k views
Are services like Hide My Ass and UnoDNS reasonably safe to use?
While in Germany, I want to keep using my Netflix account, watch PBS, CNBC. I have found following services:
A VPN: https://hidemyass.com/vpn/promo/1/5/
A DNS: http://www.unotelly.com/unodns/
I an ...
4
votes
2answers
684 views
How does DNSSec work? Are there known limitations or issues?
Based on information from this site, DNSSec is needed to protect us from a number of DNS and SSL / TLS hacks, including:
DNS spoofing, especially on wifi or shared medium
Registrars that abuse their ...
4
votes
5answers
110 views
Why can we not block DNS Amplification attack by blocking UDP packets or DNS response packet?
I mean if the attacker tries to ask all the open DNS resolver respond to a web server. The web server can just block its UDP ports.
If the all the DNS response go to a Authoritative ...
4
votes
3answers
354 views
Does DNS pinning protect against all DNS rebinding attack?
I found an example of a DNS rebinding attack scenario in the paper "Dynamic Pharming Attacks and Locked Same-origin Policies for Web Browsers".
Figure 1: An example of a dynamic pharming attack ...
4
votes
3answers
390 views
How dangerous is it that there are DNS entries for our domain that we did not register?
I was performing an DNS brute-force on our company's domain and found entries like "html" "ww" and "wwww" resolving to IPs outside of our registered block.
This sparked a debate about just how ...
4
votes
1answer
137 views
Kaminsky Bug Exploitation
I am trying to exploit the Kaminsky bug for a school assignment. The specific version of the bug that I want to exploit is sending a forged packet with false information about www.domain.com so that ...
4
votes
2answers
135 views
What risk do International Domain Names (IDN) pose?
I understand that IDN's are basically a GUI display change for domains that have a prefix of "xn--".
What should I advise companies do in regards to these domains?
For example, should companies ...
4
votes
1answer
312 views
Which security risks are associated with alternative DNS providers?
I'm considering using an alternative DNS provider on my computer. Which risks do I run if I use one?
I already know that the DNS provider may return a malicious IP address when I'm trying to access ...
4
votes
2answers
475 views
How do I find all domains hosted on a single host?
I found several websites offer a function that allows you to list all domains hosted on the same machine, e.g you supply a.com, and it tells you b.com and c.com are both hosted on the same machine as ...
4
votes
3answers
280 views
Is it harmful to redirect web bugs to localhost on hosts file?
I was checking the article hosts file on Wikipedia, and I found this:
Blocking access to servers of unwanted content by redirecting them to the local host (127.0.0.1) may have security ...
4
votes
1answer
168 views
What is the status of forced HTTPS everywhere (Strict transport security) via DNS? I only see last years draft
I'm trying to find the most recent RFC on HSTS in DNS (or rather said DNSSEC), but can only find this year old one in expired draft status
Where can I find the most current guidance on STS in DNS? If ...
4
votes
1answer
197 views
Anyone use the International Domain Name (IDN) security mitigation API's? Is there a wrapper for .NET?
The International Domain Name mitigation API's are available here for download:
http://www.microsoft.com/downloads/en/details.aspx?FamilyID=ad6158d7-ddba-416a-9109-07607425a815&displaylang=en
...
4
votes
1answer
162 views
Should content delivery depend on FCrDNS (forward-confirmed reverse DNS) look-ups and why?
First, let me clear that this isn't a duplicate of Does deliberately wrong information from a DNS server violate standards generally accepted good practices? thread, as I'm not interested in legal ...
4
votes
1answer
169 views
My DNS Name Server does not support DNSSec client queries, what alternatives do I have?
I am using a web browser to access DNSSec enabled sites. My current name server doesn't (won't) support DNSSec for at least a year. What are my alternatives?
Do any ISPs currently offer DNSSec? ...
4
votes
1answer
192 views
Does deliberately wrong information from a DNS server violate standards generally accepted good practices?
For certain host names my DNS gives me a wrong ip address (the ip address of a transparent proxy) for which inverse DNS look up does not give me back the host I originally looked up.
This is related ...
4
votes
1answer
116 views
When should a DNS entry be cached? What conditions should not be? How do I determine the TTL?
I'm writing a DNS resolver and am building a spreadsheet of when a DNS record should be cached, and not be cached... but it's harder than it first looks (to me at least).
Is there consolidated test ...
3
votes
5answers
383 views
Alternatives for DNS resolution
I was told it's a good idea not to use your ISP to resolve DNS, both for privacy issues and because it can be slow. So I wanted to change, but I've read criticism on using OpenDNS (who makes money on ...
3
votes
1answer
917 views
DNSSec (comcast) vs DNSCurve (OpenDNS)
I was previously using OpenDNS on my internal network. I found out today that comcast has switched over to DNSSec:Comcast DNSSec.
I've did a little research on DNSSec and its benefits. I ...
3
votes
1answer
212 views
How exactly would SOPA-style DNS blocking threaten the security of the Internet?
A point that keeps getting mentioned in the SOPA debate is that the DNS blocking it prescribes will cause security problems. Can somebody explain in simple terms just exactly how SOPA threatens ...
3
votes
1answer
149 views
How will users know if their session is DNSSec protected or not?
There is definite security value in having DNSSec-verified connections, however I have yet to see software indicate if the connection is secure.
Ultimately I would like my users to recognize that ...
3
votes
1answer
86 views
Why is a separate reconnaissance server needed for DNS cache poisoning?
I'm trying to understand how Metasploit's DNS BailiWicked Host Attack module works. One of the required module options is a "reconnaissance" nameserver (option RECONS).
What I understand from the ...
3
votes
2answers
128 views
Unecrypted connection to server - safe?
I am using heroku and cloudflare. I am going to release my website but I don't want do it without SSL.
Now I always need an heroku addon to add my SSL certificates which costs $20/month.
Cloudflare ...
3
votes
2answers
2k views
Listing of DNS vulnerabilities
I am currently studying how to setup DNS servers and all aspects of the DNS system. I would also like to study the security aspect. I want to use current DNS server attack on my test servers. Is there ...
3
votes
2answers
502 views
How does DNS Changer malware detection work?
This malware directs your computer to use DNS servers under control of the badguys. These DNS servers were taken over by the FBI. They were replaced with clean ones, to prevent service disruption, but ...
3
votes
3answers
244 views
Are there DNS analysis tools that could detect bad DNS results?
Are there any tools (or at least methods that would work, if no free tools currently exist) which one could use to detect false DNS results?
It would be very simply to detect an attack along the ...
3
votes
1answer
311 views
captive portal wikipedia article
Something on the wikipedia page regarding captive portals have confused me:
http://en.wikipedia.org/wiki/Captive_portal
When a client requests a website, DNS is queried by the browser. The
...
3
votes
1answer
130 views
Can NSEC domain enumeration happen for zones with wildcard records?
In DNSSEC, NSEC records are used to provide proof of nonexistence. The trouble is that these records provide pointers to existent domain names (the closest known domain in either direction) ...
