Tagged Questions

2
votes
2answers
221 views

DNS cache poisoning

What are the things the attacker needs to know from the victim to perform DNS cache poisoning ? for example : IP , Port number and Transaction number what else ?
8
votes
2answers
204 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?
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 ...
1
vote
1answer
242 views

DNS query through squid? [closed]

My IDS picked up our squid proxy server doing a dynamic DNS request. I wasn't aware squid passed DNS requests from the client to the internal DNS server. Is this possible? Snort Alert: ET POLICY ...
1
vote
1answer
81 views

DNS Cache poisioning examples, or other criteria when a client ignores a response

Is there a concise set of rules that describe what 99% percent of DNS responders accept? Conversely, are there are set of rules that define when DNS queries are invalid? Example answer I would ...
1
vote
1answer
273 views

Should Windows 2008 R2 be used as an externally facing DNS name server?

When compared to more traditional DNS name servers, what are the benefits / drawbacks of using a Windows 2008 R2 as a public ns record for a company. What limitations, or security issues would I ...
4
votes
1answer
170 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? ...
0
votes
1answer
698 views

Is OpenVPN secure in this way?

I'm familiar with OpenVPN because my home router has a builtin OpenVPN server. I would like to use OpenVPN all the time, but how do I deal with situations where I don't own the routers? ex.: in a ...
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 ...
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 ...
5
votes
2answers
968 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 ...
0
votes
1answer
229 views

Is using a local DNS cache server more secure than using a DNS server from a router?

Is using a local DNS cache server imore secure than using a DNS server from a router?
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 ...
2
votes
2answers
189 views

DNS access limitations

Im working on a script that's going to talk to a DNS on a LAN that have information about local domains. And I believe its blocking my requests. So my question is: How can you limit a DNS server to ...
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 ...
2
votes
2answers
773 views

How do the root servers get updated with my name server? Is WhoIS information always in sync with the root?

I've never understood what happens behind the scenes when I go to my registrar and enter in my name server's information. Can someone elaborate on what happens when an update is made, and how it is ...
4
votes
1answer
117 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 ...
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 ...