# Pcap Inspection {% hint style="info" %} A note about **PCAP** vs **PCAPNG**: there are two versions of the PCAP file format; **PCAPNG is newer and not supported by all tools**. You may need to convert a file from PCAPNG to PCAP using Wireshark or another compatible tool, in order to work with it in some other tools. {% endhint %} ## Online tools for pcaps * If the header of your pcap is **broken** you should try to **fix** it using: [http://f00l.de/hacking/**pcapfix.php**](http://f00l.de/hacking/pcapfix.php)**** * Extract **information** and search for **malware** inside a pcap in [**PacketTotal**](https://packettotal.com)**** * Search for **malicious activity** using [**www.virustotal.com**](https://www.virustotal.com) and [**www.hybrid-analysis.com**](https://www.hybrid-analysis.com)**** ## Extract Information The following tools are useful to extract statistic, files... ### Wireshark {% hint style="info" %} **If you are going to analyze a PCAP you basically must to know how to use Wireshark** {% endhint %} You can find some Wireshark trick in: {% content-ref url="wireshark-tricks.md" %} [wireshark-tricks.md](wireshark-tricks.md) {% endcontent-ref %} ### Xplico Framework ****[**Xplico **](https://github.com/xplico/xplico)_(only linux)_** **can **analyze** a **pcap** and extract information from it. For example, from a pcap file Xplico extracts each email (POP, IMAP, and SMTP protocols), all HTTP contents, each VoIP call (SIP), FTP, TFTP, and so on. #### Install ```bash sudo bash -c 'echo "deb http://repo.xplico.org/ $(lsb_release -s -c) main" /etc/apt/sources.list' sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 791C25CE sudo apt-get update sudo apt-get install xplico ``` #### Run ``` /etc/init.d/apache2 restart /etc/init.d/xplico start ``` Access to _**127.0.0.1:9876 **_with credentials _**xplico:xplico**_ Then create a **new case**, create a **new session** inside the case and **upload the pcap** file. ### NetworkMiner Like Xplico it is a tool to **analyze and extract objects from pcaps**. It has a free edition that you can **download **[**here**](https://www.netresec.com/?page=NetworkMiner). It works with **Windows**.\ This tool is also useful to get **other information analysed** from the packets in order to be able to know what was happening there in a **quick** way. ### NetWitness Investigator You can download [**NetWitness Investigator from here**](https://www.rsa.com/en-us/contact-us/netwitness-investigator-freeware)** (It works in Windows)**.\ This is another useful tool that **analyse the packets** and sort the information in a useful way to **know what is happening inside**. ![](<../../../.gitbook/assets/image (567) (1) (1).png>) ### [BruteShark](https://github.com/odedshimon/BruteShark) * Extracting and encoding usernames and passwords (HTTP, FTP, Telnet, IMAP, SMTP...) * Extract authentication hashes and crack them using Hashcat (Kerberos, NTLM, CRAM-MD5, HTTP-Digest...) * Build visual network diagram (Network nodes & users) * Extract DNS queries * Reconstruct all TCP & UDP Sessions * File Carving ### Capinfos ``` capinfos capture.pcap ``` ### Ngrep If you are **looking** for **something** inside the pcap you can use **ngrep**. And example using the main filters: ```bash ngrep -I packets.pcap "^GET" "port 80 and tcp and host 192.168 and dst host 192.168 and src host 192.168" ``` ### Carving Using common carving techniques can be useful to extract files and information from the pcap: {% content-ref url="../partitions-file-systems-carving/file-data-carving-recovery-tools.md" %} [file-data-carving-recovery-tools.md](../partitions-file-systems-carving/file-data-carving-recovery-tools.md) {% endcontent-ref %} ### Capturing credentials You can us tools like [https://github.com/lgandx/PCredz](https://github.com/lgandx/PCredz) to parse credentials from a pcap or a live interface. ## Check Exploits/Malware ### Suricata #### Install and setup ``` apt-get install suricata apt-get install oinkmaster echo "url = http://rules.emergingthreats.net/open/suricata/emerging.rules.tar.gz" >> /etc/oinkmaster.conf oinkmaster -C /etc/oinkmaster.conf -o /etc/suricata/rules ``` #### Check pcap ``` suricata -r packets.pcap -c /etc/suricata/suricata.yaml -k none -v -l log ``` ### YaraPcap ****[**YaraPCAP**](https://github.com/kevthehermit/YaraPcap) is a tool that * Reads a PCAP File and Extracts Http Streams. * gzip deflates any compressed streams * Scans every file with yara * writes a report.txt * optionally saves matching files to a Dir ### Malware Analysis Check if you can find any fingerprint of a known malware: {% content-ref url="../malware-analysis.md" %} [malware-analysis.md](../malware-analysis.md) {% endcontent-ref %} ## Zeek > Zeek is a passive, open-source network traffic analyzer. Many operators use Zeek as a network security monitor (NSM) to support investigations of suspicious or malicious activity. Zeek also supports a wide range of traffic analysis tasks beyond the security domain, including performance measurement and troubleshooting. Basically, logs created by `zeek` aren't **pcaps**. Therefore you will need to use **other tools** to analyse the logs where the **information **about the pcaps are. ### Connections Info ```bash #Get info about longest connections (add "grep udp" to see only udp traffic) #The longest connection might be of malware (constant reverse shell?) cat conn.log | zeek-cut id.orig_h id.orig_p id.resp_h id.resp_p proto service duration | sort -nrk 7 | head -n 10 10.55.100.100 49778 65.52.108.225 443 tcp - 86222.365445 10.55.100.107 56099 111.221.29.113 443 tcp - 86220.126151 10.55.100.110 60168 40.77.229.82 443 tcp - 86160.119664 #Improve the metrics by summing up the total duration time for connections that have the same destination IP and Port. cat conn.log | zeek-cut id.orig_h id.resp_h id.resp_p proto duration | awk 'BEGIN{ FS="\t" } { arr[$1 FS $2 FS $3 FS $4] += $5 } END{ for (key in arr) printf "%s%s%s\n", key, FS, arr[key] }' | sort -nrk 5 | head -n 10 10.55.100.100 65.52.108.225 443 tcp 86222.4 10.55.100.107 111.221.29.113 443 tcp 86220.1 10.55.100.110 40.77.229.82 443 tcp 86160.1 #Get the number of connectionssummed up per each line cat conn.log | zeek-cut id.orig_h id.resp_h duration | awk 'BEGIN{ FS="\t" } { arr[$1 FS $2] += $3; count[$1 FS $2] += 1 } END{ for (key in arr) printf "%s%s%s%s%s\n", key, FS, count[key], FS, arr[key] }' | sort -nrk 4 | head -n 10 10.55.100.100 65.52.108.225 1 86222.4 10.55.100.107 111.221.29.113 1 86220.1 10.55.100.110 40.77.229.82 134 86160.1 #Check if any IP is connecting to 1.1.1.1 cat conn.log | zeek-cut id.orig_h id.resp_h id.resp_p proto service | grep '1.1.1.1' | sort | uniq -c #Get number of connections per source IP, dest IP and dest Port cat conn.log | zeek-cut id.orig_h id.resp_h id.resp_p proto | awk 'BEGIN{ FS="\t" } { arr[$1 FS $2 FS $3 FS $4] += 1 } END{ for (key in arr) printf "%s%s%s\n", key, FS, arr[key] }' | sort -nrk 5 | head -n 10 ### RITA #Something similar can be done with the tool rita rita show-long-connections -H --limit 10 zeek_logs +---------------+----------------+--------------------------+----------------+ | SOURCE IP | DESTINATION IP | DSTPORT:PROTOCOL:SERVICE | DURATION | +---------------+----------------+--------------------------+----------------+ | 10.55.100.100 | 65.52.108.225 | 443:tcp:- | 23h57m2.3655s | | 10.55.100.107 | 111.221.29.113 | 443:tcp:- | 23h57m0.1262s | | 10.55.100.110 | 40.77.229.82 | 443:tcp:- | 23h56m0.1197s | #Get connections info from rita rita show-beacons zeek_logs | head -n 10 Score,Source IP,Destination IP,Connections,Avg Bytes,Intvl Range,Size Range,Top Intvl,Top Size,Top Intvl Count,Top Size Count,Intvl Skew,Size Skew,Intvl Dispersion,Size Dispersion 1,192.168.88.2,165.227.88.15,108858,197,860,182,1,89,53341,108319,0,0,0,0 1,10.55.100.111,165.227.216.194,20054,92,29,52,1,52,7774,20053,0,0,0,0 0.838,10.55.200.10,205.251.194.64,210,69,29398,4,300,70,109,205,0,0,0,0 ``` ### DNS info ```bash #Get info about each DNS request performed cat dns.log | zeek-cut -c id.orig_h query qtype_name answers #Get number of times each domain was requestedand get top 10 cat dns.log | zeek-cut query | sort | uniq | rev | cut -d '.' -f 1-2 | rev | sort | uniq -c | sort -nr | head -n 10 #Get all the IPs cat dns.log | zeek-cut id.orig_h query | grep 'example\.com' | cut -f 1 | sort | uniq -c #Sort the most common dnsrecord request (should be A) cat dns.log | zeek-cut qtype_name | sort | uniq -c | sort -nr #See top DNS domain requested with rita rita show-exploded-dns -H --limit 10 zeek_logs ``` ## Other pcap analysis tricks {% content-ref url="dnscat-exfiltration.md" %} [dnscat-exfiltration.md](dnscat-exfiltration.md) {% endcontent-ref %} {% content-ref url="wifi-pcap-analysis.md" %} [wifi-pcap-analysis.md](wifi-pcap-analysis.md) {% endcontent-ref %} {% content-ref url="usb-keystrokes.md" %} [usb-keystrokes.md](usb-keystrokes.md) {% endcontent-ref %}