NETWORK ANOMALY DETECTION

• US 20170295196A1
• Filed: 04/10/2015
• Published: 10/12/2017
• Est. Priority Date: 04/10/2015
• Status: Active Grant

• Current Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Original Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Inventors: ARNELL, Simon Ian, CASASSA MONT, Marco, GRAVES, David Andrew, REYNOLDS, Edward, SAUNDERS, Niall Lawrence
• Granted Patent: US 10,686,814 B2
• Time in Patent Office: Days
• CPC Class Codes: G06F 21/552 involving long-term monitoring or reporting
• CPC Class Codes: H04L 2463/144 Detection or countermeasures against botnets
• CPC Class Codes: H04L 43/12 Network monitoring probes
• CPC Class Codes: H04L 61/4511 using domain name system [DNS]
• CPC Class Codes: H04L 63/14 for detecting or protecting against malicious traffic
• CPC Class Codes: H04L 63/1408 by monitoring network traffic monitoring network traffic per se H04L43/00
• CPC Class Codes: H04L 63/1425 Traffic logging, e.g. anomaly detection
• CPC Class Codes: H04L 69/40 for recovering from a failure of a protocol instance or entity, e.g. service redundancy protocols, protocol state redundancy or protocol service redirection management of faults, events, alarms or notifications in data switching networks H04L41/06

Abstract

Examples relate to detecting network anomalies. In one example, a computing device may: receive, from each of a plurality of packet capture devices of a private network, domain name system (DNS) query packets that were sent by a particular client computing device operating on the private network, each DNS query packet specifying i) a destination DNS server, ii) a query domain name, and iii) a source address that specifies the particular client computing device; provide at least one of the DNS query packets to a DNS traffic analyzer that is trained to identify DNS anomalies based on characteristics of the DNS query packets; receive anomaly output from the DNS traffic analyzer, the anomaly output indicating a DNS anomaly that was identified for the DNS query packets; and in response to receiving the anomaly output, provide a user device with data specifying the identified DNS anomaly.

Claims

1. A non-transitory machine-readable storage medium encoded with instructions executable by a hardware processor of a computing device for network anomaly detection, the machine-readable storage medium comprising instructions to cause the hardware processor to:

receive, from each of a plurality of packet capture devices of a private network, domain name system (DNS) query packets that were sent by a particular client computing device operating on the private network, each DNS query packet specifying i) a destination DNS server, ii) a query domain name, and iii) a source address that specifies the particular client computing device;

provide at least one of the DNS query packets to a DNS traffic analyzer that is trained to identify DNS anomalies based on characteristics of the at least one DNS query packets;

receive anomaly output from the DNS traffic analyzer, the anomaly output indicating a DNS anomaly that was identified for the at least one DNS query packets; and

in response to receiving the anomaly output, provide a user device with data specifying the identified DNS anomaly.

2. The storage medium of claim 1, wherein:

the particular client computing device comprises a virtual machine;

the private network comprises a cloud computing network; and

each of the plurality of packet capture devices are implemented in a router included in the cloud computing network.

3. The storage medium of claim 1, wherein the DNS anomaly comprises:

a change in DNS configuration of the particular client computing device;

a volume of DNS traffic that exceeds a predefined DNS traffic volume threshold;

pseudo-randomly generated domain names specified as the query domain name for at least one of the DNS query packets;

or

a domain name unrecognized by an internal DNS operating in the private network.

4. The storage medium of claim 1, wherein the instructions further cause the processor to:

exclude, from the DNS query packets, whitelist DNS packets that specify a whitelisted domain name included in a whitelist of domain names; and

exclude, from the DNS query packets, blacklist DNS packets that specify a blacklisted domain name included in a blacklist of domain names.

5. The storage medium of claim 1, wherein the particular client computing device is one of a plurality of client computing devices managed by a client, and wherein the instructions further cause the processor to:

receive, from each of a second plurality of packet capture devices of the private network, second DNS query packets that were sent by a second client computing device that is included in the plurality of client computing devices, each second DNS query packet specifying i) a destination DNS server, ii) a query domain name, and iii) a source address that specifies the second client computing device;

combine at least one of the second DNS query packets with the DNS query packets provided to the DNS traffic analyzer, and wherein the anomaly output from the DNS traffic analyzer indicates a client DNS anomaly, the client DNS anomaly comprising an anomaly that was identified based on both i) the DNS query packets of the particular client computing device, and ii) the second DNS query packets of the second client computing device.

6. A computing device for network anomaly detection, the computing device comprising:

a hardware processor; and

a data storage device storing instructions that, when executed by the hardware processor, cause the hardware processor to;

obtain, from a plurality of network packet capture devices of a private network, a set of domain name system (DNS) packets, each DNS packet i) being addressed to a DNS server, and ii) having a source address that specifies a client computing device included in the private network;

identify, from the set of DNS packets, whitelist DNS packets that specify a whitelisted domain name included in a whitelist of domain names;

identify, from the set of DNS packets, blacklist DNS packets that specify a blacklisted domain name included in a blacklist of domain names;

identify, from the set of DNS packets, a set of unknown DNS packets by excluding, from the set of DNS packets, each whitelist DNS packet and blacklist DNS packet;

analyze, for a particular client computing device included in the private network, unknown DNS packets having a particular source address that specifies the particular client computing device; and

identify, based on at least one characteristic of the analyzed unknown DNS packets, a DNS anomaly for the client computing device.

7. The computing device of claim 6, wherein a DNS anomaly is identified in response to determining that the at least one characteristic of the analyzed unknown DNS packets indicates:

a change in DNS configuration;

a volume of DNS traffic that exceeds a predefined DNS traffic volume threshold;

pseudo-randomly generated domain names;

or

a domain name unrecognized by an internal DNS operating in the private network.

8. The computing device of claim 6, wherein:

the client computing device of each DNS packet comprises a virtual machine;

the private network comprises a cloud computing network; and

each of the plurality of network packet capture devices is implemented in a router included in the cloud computing network.

9. The computing device of claim 6, wherein the instructions further cause the hardware processor to:

identify a change in a DNS configuration of the particular client computing device;

and wherein the unknown DNS packets are analyzed by comparing, for each domain name included in each unknown DNS packet, a first address resolved by a first DNS server to a second address resolved by a second DNS server.

10. The computing device of claim 9, wherein a DNS anomaly is identified for the client computing device in response to determining, based on the comparison of the first address and the second address, that a discrepancy exists.

11. A method for network anomaly detection, implemented by a hardware processor, the method comprising:

obtaining, from a plurality of network packet capture devices of a private network, domain name system (DNS) query packets that were sent by a plurality of client computing devices operating on the private network, each DNS query packet specifying i) a destination DNS server, ii) a query domain name, and iii) a source address that specifies one of the plurality of client computing devices;

identifying, from the DNS query packets, a set of client DNS packets for a particular client, each client DNS packet specifying a source address associated with the particular client;

identifying, based on at least one characteristic of the set of client DNS packets, a DNS anomaly for the particular client; and

providing, to a user device, data specifying the DNS anomaly.

12. The method of claim 11, wherein at least two client computing devices of the plurality of client computing devices are specified by the client DNS packets.

13. The method of claim 12, wherein the DNS anomaly is identified based on client DNS packets that specify source addresses of each of the at least two client computing devices.

14. The method of claim 12, wherein the DNS anomaly is identified based on client DNS packets that specify the source address of only one of the at least two client computing devices.

15. The method of claim 12, wherein:

each of the at least two client computing devices comprise a virtual machine;

the private network comprises a cloud computing network; and

each of the plurality of network packet capture devices is implemented in a router included in the cloud computing network.