Goline Logo

News

  • Route RPKI validation April 1st, 2022
    RPKI is a security framework by which network owners can validate and secure the critical route updates or Border Gateway Protocol (BGP) announcements between public Internet networks. BGP is essentially the central nervous system of the Internet and one of its fundamental building blocks. The main function of BGP is to facilitate efficient routing between Autonomous Systems (AS), by building and maintaining the Internet routing table. The Internet routing table is effectively the navigation system of the Internet and without it, traffic would be unable to flow between its constituent networks. Unfortunately, routing equipment alone cannot distinguish between legitimate and malicious routing announcements,...
  • RIPE – Atlas Anchor February 17th, 2022
    We have become an even more integral part of the RIPE Atlas project by hosting an anchor, a device that allows for latency analysis of traffic between autonomous systems.https://atlas.ripe.net/probes/7073/RIPE Atlas anchors play an integral role in the RIPE Atlas network by acting both as enhanced RIPE Atlas probes with more measurement capacity, as well as regional measurement targets within the greater RIPE Atlas network. Anchors are able to perform many more measurements than a regular RIPE Atlas probe, and the large amount of data they collect is made available to everyone. In addition, anchors act as powerful targets that can...
  • MANRS June 20th, 2020
    GOLINE firmly believes in initiatives to protect networks, improve security and resilience of the global routing system. Therefore we decided to support the MANRS project and join as participants.Mutually Agreed Norms for Routing Security (MANRS) is a global initiative, supported by the Internet Society, that provides crucial fixes to reduce the most common routing threats. MANRS offers specific actions via four programs for Network Operators, Internet Exchange Points, CDN and Cloud Providers, and Equipment Vendors. Requirements for Participation Please read the full MANRS Actions document before applying. You can become a participant if you meet these requirements: You (or your company) support...

Windows 2012 R2 DNS (Avoid spoofing – increase SocketPoolSize)

Paolo Caparrelli Windows 22 June 2022

 

Randomize your DNS source ports

There are some DNS attacks that can take advantage of the predictability of the source port for DNS responses a computer sends out. The predictability can allow the attacker to hijack a response to a DNS client and send the client to a site under the attacker’s control. You can reduce the risk of this attack being successful by increasing the number of source ports available for randomization.

You do this by increasing the size of the socket pool. For Windows Server 2008 R2 DNS servers, the default size of the socket pool is 2500. You can increase the number of available sockets for randomization to a maximum value of 10,000.

Use the following dnscmd command to change the socket pool value:

dnscmd /Config /SocketPoolSize<value>

If you want to see the current size of the socket pool, then use this dnscmd command:

Dnscmd /Info /SocketPoolSize

You can also exclude ranges of ports used by the socket pool, using the followingdnscmd command:

dnscmd /Config /SocketPoolExcludedPortRanges<excluded port ranges>

Keep in mind that it will take more memory to support more sockets. On Windows Server 2008 R2, around 2.5 KB of memory is allocated for each socket, plus 7.2 KB of memory per receive buffer. The number of receive buffers is two on a single or dual processor server, and equal to the number of CPUs if more than two are present.

0 0 votes
Article Rating
Subscribe
Notify of
guest
0 Comments
Inline Feedbacks
View all comments
0
Would love your thoughts, please comment.x
()
x