Device Security Analysis
Food bank donation site: sprayed admin logins and a receipt download trick
- Units 1, 3, 4 and 5
- 14 points
- About 50 minutes
You get several sources from one device, such as its firewall rules, system and web logs, a file listing with permissions, and its acceptable use policy. You explain how the policy protects the device, find the evidence of attacks in the logs, read and write file permissions with chmod, change a firewall rule and say what that changes, and suggest ways to stop the attack. On the exam: The only free-response question: Section II, 1 question in 50 minutes, 30% of the exam score, taken in Bluebook (fully digital) after the 60-question, 80-minute multiple-choice section. The CED sample gives 6 sources about one device and has parts A to E with 14 one-point subparts (A 2, B 2, C 3, D 3, E 4). It assesses Mitigate Risk and Detect Attacks, and you must cite specific evidence, like log line numbers, IP addresses, file names and rule numbers.
The question and its sources
The following sources all come from the same device, the donation website server for Harbor Lights Food Bank (IP address 192.0.2.180), and were gathered during a security review. Use them to answer parts A, B, C, D and E. Label each subpart (i, ii, iii, iv) in your answer, and cite specific evidence such as source numbers, line numbers, IP addresses, file names and rule numbers.
Source 1: Device firewall settings
| Rule | Action | Source | Destination | Direction | Port | Service |
|---|---|---|---|---|---|---|
| 1 | Allow | ALL | 192.0.2.180 | Inbound | 443 | HTTPS |
| 2 | Allow | ALL | 192.0.2.180 | Inbound | 80 | HTTP |
| 3 | Allow | 192.0.2.0/24 | 192.0.2.180 | Inbound | 22 | SSH |
| 4 | Deny | ALL | ALL | Inbound | ALL | ALL |
Source: Hypothetical device records written for this practice question
Source 2: Admin login log (sudo tail -n 11 /var/log/site-admin.log)
| Line | Entry |
|---|---|
| 1 | May 19 16:10:03 donate site-admin[611]: login ok user=webmaster ip=192.0.2.33 |
| 2 | May 20 01:15:03 donate site-admin[611]: login failed user=admin ip=198.51.100.77 |
| 3 | May 20 01:15:06 donate site-admin[611]: login failed user=coordinator ip=198.51.100.77 |
| 4 | May 20 01:15:09 donate site-admin[611]: login failed user=volunteer1 ip=198.51.100.77 |
| 5 | May 20 01:15:12 donate site-admin[611]: login failed user=volunteer2 ip=198.51.100.77 |
| 6 | May 20 01:15:15 donate site-admin[611]: login failed user=treasurer ip=198.51.100.77 |
| 7 | May 20 01:15:18 donate site-admin[611]: login failed user=webmaster ip=198.51.100.77 |
| 8 | May 20 01:15:21 donate site-admin[611]: login failed user=events ip=198.51.100.77 |
| 9 | May 20 01:15:24 donate site-admin[611]: login failed user=outreach ip=198.51.100.77 |
| 10 | May 20 09:31:12 donate kernel: [UFW BLOCK] IN=eth0 OUT= SRC=198.51.100.44 DST=192.0.2.180 PROTO=TCP DPT=22 |
| 11 | May 20 11:02:40 donate kernel: [UFW BLOCK] IN=eth0 OUT= SRC=203.0.113.9 DST=192.0.2.180 PROTO=TCP DPT=3306 |
Source: Hypothetical device records written for this practice question. 198.51.100.44 is the home internet address of the food bank's volunteer webmaster
Source 3: Web server access log (sudo tail -n 7 /var/log/nginx/access.log)
| Line | Entry |
|---|---|
| 1 | 198.51.100.150 - - [20/May/2026:10:12:30 -0400] "POST /donate HTTP/1.1" 302 96 "-" "Mozilla/5.0 (iPhone)" |
| 2 | 198.51.100.150 - - [20/May/2026:10:12:41 -0400] "GET /receipt?file=receipt_10233.pdf HTTP/1.1" 200 48211 "-" "Mozilla/5.0 (iPhone)" |
| 3 | 203.0.113.212 - - [20/May/2026:10:40:02 -0400] "GET /receipt?file=receipt_10234.pdf HTTP/1.1" 200 48300 "-" "curl/8.4.0" |
| 4 | 203.0.113.212 - - [20/May/2026:10:40:05 -0400] "GET /receipt?file=[path using repeated parent-directory steps (../) to reach /etc/passwd] HTTP/1.1" 200 1822 "-" "curl/8.4.0" |
| 5 | 203.0.113.212 - - [20/May/2026:10:40:07 -0400] "GET /receipt?file=[path using repeated parent-directory steps (../) to reach /etc/shadow] HTTP/1.1" 403 162 "-" "curl/8.4.0" |
| 6 | 203.0.113.212 - - [20/May/2026:10:40:11 -0400] "GET /receipt?file=[path using parent-directory steps (../) to reach /var/www/donate/site.conf] HTTP/1.1" 200 412 "-" "curl/8.4.0" |
| 7 | 192.0.2.33 - webmaster [20/May/2026:10:55:20 -0400] "GET /admin/campaigns HTTP/1.1" 200 6120 "-" "Mozilla/5.0 (Windows NT 10.0)" |
Source: Hypothetical device records written for this practice question. Bracketed text describes request content that has been removed
Source 4: File listing
$ ls -l /var/www/donate
-rw-rw-r-- 1 webmaster www-data 220416 May 20 06:00 donors.csv
-rw-r--r-- 1 webmaster www-data 412 Apr 02 13:40 site.conf
-rw-r--r-- 1 webmaster www-data 9120 Mar 14 10:05 receipt_template.html
-rwxrwxrwx 1 webmaster webmaster 760 Feb 11 09:22 cleanup.sh
-rw-rw-r-- 1 webmaster www-data 288 May 01 12:00 admin_users.txt
Source: Hypothetical device records written for this practice question
Source 5: Harbor Lights website software policy
Required:
• Website software and plugins must be updated within 7 days of a security update.
• Only plugins approved by the volunteer IT lead may be installed on the website.
Permitted:
• Volunteers may edit donation campaign pages through the admin site.
Prohibited:
• Card numbers may not be stored on the web server; all payments go through the payment processor.
• Volunteers may not share admin logins.
Source: Hypothetical device records written for this practice question
Suggested time: 50 minutes
Your answers are saved in this browser as you type.
Part (A)
2 points(i) Explain how one rule in the website software policy in Source 5 protects the device from a specific threat. (ii) Explain how one rule that is already in the website software policy could be changed to make the device more secure. Give a specific example of the changed rule.
0 / 2,500 characters
Part (B)
2 pointsSource 2 contains evidence of an online password attack on the admin site. (i) Describe the evidence in the log that indicates a password attack. Cite specific line numbers and entries. (ii) Identify the IP address of the adversary.
0 / 2,500 characters
Part (C)
3 points(i) Choose one file in /var/www/donate (Source 4). Explain what its owner, its group and all other users can each do with the file, and how its permission string shows this. Name the file. (ii) Without removing every permission from every user, describe one change to the permissions of one file in Source 4 that would limit access for some users. Name the file. (iii) Write one or more chmod commands that make the change you described in part C (ii).
0 / 2,500 characters
Part (D)
3 points(i) Explain why one connection attempt recorded in the logs was blocked by the device's firewall. Cite the log entry and the firewall rule involved. (ii) Other than allowing all traffic on all ports, describe a change to one existing rule in Source 1 that would let the connection you identified in part D (i) through. (iii) Besides letting that connection through, describe one other effect your change in part D (ii) would have on network traffic to or from the device.
0 / 2,500 characters
Part (E)
4 pointsBesides the password attack in part B, Source 3 shows evidence of a second attack. (i) Determine the type of attack. (ii) Describe the specific information in the sources that indicates this attack. Cite the source and line numbers. (iii) Describe one way an automated system could stop this attack while it is happening. (iv) Other than a firewall, an IDS, an IPS or an AI tool, identify one countermeasure that could prevent, mitigate or deter this attack.
0 / 2,500 characters
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