The Domain Name System (DNS) translates Internet domain and host names to IP addresses.

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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 ...
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823 views

Security implications of an exploited router

So I completely understand that routers and local networks need to be kept locked down, etc. What real security threats can come about from an attacker who has remotely accessed (telnet or web gui) ...
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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 ...
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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 ...
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DNS spoofing of linux distribution repositories

Question(s) Is it possible to "redirect" linux-update-repos via DNS spoofing (e.g. DNS cache poisoning) to a malicious website, so that harmful software (updates) will be installed, when running the ...
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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 ...
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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 ...
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749 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 ...
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Dnscrypt vs Dnscurve?

Which is better for highest privacy and security ? I've read both of them and i still don't understand the differences between them... Can anyone explain what features is exclusive to one? My most ...
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ISP glitch or a malware? Has this ever happened to you?

Brief background: I consider myself a relatively paranoid power-user, if not an absolute pro. I regularly update my AV and keep up with all the latest updates on my Windows 7 machine. But what ...
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How Do I Troubleshoot a Browser Hijack on a Mac?

My Mac is getting weird redirects with Safari and Chrome, however not with Mozilla Firefox. Since I cannot find software to do malware removal on Apple products or any good information, I am at a loss ...
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209 views

Attack on authoritative DNS server with high TTLs

The way DNS works, resolvers cache query results per TTL defined in the response. Consider an authoritative DNS server that is compromised, its main A record set to a different IP and TTL of that ...
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632 views

How do I identify which PC made a suspicious DNS query?

Our IDS detected a suspicious DNS packet going to a Botnet (or similar). Since that DC is a recursive relay, how can we identify the client who made that request. (Windows DNS server)
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DNSspoof not working

My aim is to DNSspoof. My network is using a wireless router with the address 192.168.1.1 and primary DNS is the same as the router address. I have enabled Kernel IP forward in Linux. DNS host file ...
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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 ...
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To DMZ, or not to DMZ

So for an assignment, we need to create a scheme (and eventually also the set-up) of a couple of servers in a network. The 'networks' are: Internal network DMZ The internet And the servers we ...
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743 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 ...
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301 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 ...
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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 ...
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DNS Spoofing vs ARP spoofing, the relationship?

As I understand, ARP spoofing can only be done on the LAN-side of the router? DNS spoofing, can that be done either side of the router? In order to do DNS spoofing, do you need to perform ARP ...
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218 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 ...
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1answer
196 views

How important is split-horizon DNS?

Split DNS returns different results depending on the source IP. It's commonly promoted as significant security measure for internal resources, for limiting enumeration and discovery. I've had many ...
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263 views

DNS Rebinding attack - will the victim's browser send cookies?

How does a DNS Rebinding attack works? How can it violate the Same-origin policy? Will the victim's browser send cookies to the remote server (specified by IP), when the domain is not the same as is ...
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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 ...
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276 views

How can I determine the domain controller when it's not in DNS?

On a penetration test going in blind for an organization, meaning no knowledge of network topology of design, no idea what the domain(s) might be, and domain controller is not apparent in DNS...how ...
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575 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 ...
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My dlink router seems to be compromised

By chance I read today about this huge vulnerability regarding my router Dlink DIR-600. ( http://www.s3cur1ty.de/m1adv2013-003 ) Just out of curiosity about what I would find, I tried to send some ...
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Is my ISP BGP/DNS hijacking?

I've noticed some very suspicious activity from my ISP. Sometimes I would notice that when I ping google.com it would resolve to an IP which is owned by my ISP. I currently don't have an example ...
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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 ...
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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 ...
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1answer
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proxychains + dnscrypt + tor

I'm currently working in Kali and I'm trying to boost my security and anonymity online. Please, bear with me for I am no expert yet. Googling and searching here has yielded useful info but not enough ...
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204 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 ...
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Why do browsers or operating systems not have default DNSSEC validation?

Many resolvers (including TLDs and Root TLDs) support DNSSEC, also Google's OpenDNS servers support it. Yet it isn't checked on the client side by default. Why is this?
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What's stopping DANE? [closed]

As I understand it, DANE (RFC 6698) is a promising candidate for addressing issues with current TLS Trust Anchors (i.e. Trust Anchors). My attempt at explaining the issue: Currently, CAs are ...
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Does using Google DNS make extensions like AdBlock Plus useless?

As many of you probably do, I am not using my ISP DNS because of very low performance, and I am using Google's primary and secondary DNS (8.8.8.8 and 8.8.4.4) which are good speed-wise but, knowing ...
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How does DigitalOcean DNS verify the owner of a domain?

Say you purchase a domain on Namecheap, but want to host DNS on DigitalOcean. DigitalOcean, says to simply tell your registrar to use DO's nameservers, then set up your DNS for that domain on DO. ...
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1answer
272 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 ...
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Is DNSSEC immune to stripping signatures?

In my opinion, it should be possible to forge DNS reply so it doesn't include DS/RRSIG/... parts for any request, thus bypassing DNSSEC validation of resolved domain. Is DNSSEC system immune to this ...
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237 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 ...
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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 ...
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Amazon keeps asking for login/cc info via unsecure page - DNS hijack?

All my computers in the house will not connect to Amazon.com, but some unsecure (http) Amazon login page. This is the second time I'm having this issue. The first time I resolved it by changing my ...
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1answer
281 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? ...
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1answer
92 views

Are there any statistics about packet filtering to prevent IP spoofing on the internet?

DDoS attacks via spoofed DNS(sec) are daily news for the last few years, but packet filtering should prevent IP spoofing on the internet. I tried (as an exercise) to spoof a packet on my VPS and on ...
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356 views

Firewall egress filtering by domain

In our production environment, we are connecting to a few core external service providers though their APIs, and are required to have all other services blocked (PCI DSS). We currently have a ...
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327 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. Has anyone used them since they were first published in 2006? Are there any pending updates to them (I can't find a ...
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3answers
813 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 ...
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1answer
443 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 ...
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491 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) ...
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How does the “Privacy Protection” option from domain names registrars work?

Some domain names registrars are offering a "Privacy Protection" option to hide your registrant details. Your whois infos will then refer to the "privacy company" providing this service instead of the ...
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Investigating a possible rogue DNS Server (maybe DNSChanger)

One of the users of our RouterCheck tool was complaining about random popups containing ads in Spanish and Russian. Upon investigation, we found that the DNS settings on his router were changed to ...