Cybersecurity Triage
Read-onlyFind Common Admin Probe Paths
You need to find repeated requests for common administrative or login-looking paths in a web log.
Command
awk '$7 ~ /(admin|login|wp-|phpmyadmin)/ {print $1, $7, $9}' /var/log/nginx/access.log | sort | uniq -c | sort -nr | headBefore you run this
System impact: Read-only. Low when scoped to the shown target.
When not to use it: Do not assume a keyword match means compromise; this only shows requested paths.
Expected output
Counts with source IP, requested path, and HTTP status.
System impact
Read-only. Nothing changes. The command filters log lines by path keywords and counts repeated combinations.
May require elevated permissions on protected paths or service-owned files.
Recovery / rollback: no state is changed.
When to use it
Use this to spot broad internet background noise and decide whether a path is being repeatedly requested.
When not to use it
Do not assume a keyword match means compromise; this only shows requested paths.
next steps
Related commands
Spot Unusual HTTP Methods in Access Logs
Most site traffic is boring. The weird methods are worth a look.
awk '$6 !~ /^"(GET|POST|HEAD|OPTIONS)$/ {print $1, $6, $7, $9}' /var/log/nginx/access.log | sort | uniq -c | sort -nr
Count the Most Common User Agents
A strange traffic spike often has a strange user agent.
awk -F'"' '{print $6}' /var/log/nginx/access.log | sort | uniq -c | sort -nr | head
Find Clients Repeating the Same Path
The suspicious pattern is sometimes one client hammering one URL.
awk '{key=$1 " " $7; count[key]++} END {for (k in count) if (count[k] >= 5) print count[k], k}' /var/log/nginx/access.log | sort -nr | head
Find Paths Repeatedly Returning 404
One missing URL is normal. A repeated missing URL is a signal.
awk '$9==404 {count[$7]++} END {for (path in count) if (count[path] >= 3) print count[path], path}' /var/log/nginx/access.log | sort -nr | head
Find the IPs Creating the Most 4xx Noise
One address can turn a normal access log into a wall of failed requests.
awk '$9 ~ /^4/ {count[$1]++} END {for (ip in count) print count[ip], ip}' /var/log/nginx/access.log | sort -nr | head
Study mapping
Use this as independent command practice: read the notes, predict the output, then compare it with the example before using a real shell.
Independent study support only. No affiliation, endorsement, exam dumps, or real exam questions.