Stretch tasks Network Security: Threats and Prevention

Round 1: Quiz Blitz

1. Worm A virus needs a host file and someone to open it. A worm spreads on its own.
2. Encrypts files and demands payment for the key The victim's own files are held to ransom.
3. False It stops intercepted data being understood. The data can still be captured.
4. Phishing Phishing targets human trust, not a software flaw.
5. Long, strong passwords; Limiting the number of login attempts Strong passwords take far longer to guess, and attempt limits stop the guessing.
6. Validating all input Checking input, and keeping data separate from code, stops it running as a query.
7. penetration testing Penetration testing finds weaknesses so they can be fixed before criminals find them.
8. Inspects network traffic and blocks anything that breaks its rules A firewall filters traffic. Anti-malware software scans files.
9. True Traffic from thousands of addresses is far harder to block.
10. Shouldering Shouldering, or shoulder surfing, is watching someone enter a PIN or password.
11. Staff training Social engineering targets people, so the defence is teaching people.
12. It disguises itself as legitimate software; The user installs it willingly A Trojan tricks the user into installing it, like the wooden horse.

Round 2: Quick Fire

1. • A virus attaches to a host file and spreads when a user opens or shares it
   • A worm spreads by itself across a network, with no user action
   Model answer

   A virus attaches itself to a host file and only spreads when a user opens or shares that file. A worm spreads by itself across a network, with no user action at all.

2. • A server is flooded with requests
   • So it cannot respond to genuine users
   Model answer

   A server is flooded with so many requests that it cannot respond to genuine users, so the service becomes unavailable.

3. • Each user can reach only what their role needs
   • This limits the damage a compromised account, or a mistake, can do
   Model answer

   Each user is given permission to reach only what their role needs, so if an account is compromised, or someone makes a mistake, the damage is limited.

4. • Phishing: a fake email or message asking for it
   • Blagging: pretending to be someone trusted, such as IT support
   • Shouldering: watching them type it
   • A name generator quiz that collects security answers
   Model answer

   Phishing: sending a fake email that looks like it is from their bank and asks them to confirm their password. Blagging: phoning them while pretending to be from IT support and asking for it.

Round 3: Big Think

1. • Malware, such as ransomware
   • Prevented by up-to-date anti-malware and a firewall
   • Phishing or another social engineering attack
   • Prevented by staff training
   • A brute force attack on passwords
   • Prevented by strong passwords and limited login attempts
   • Interception or SQL injection
   • Prevented by encryption or input validation
   Model answer

   Malware, such as ransomware, could encrypt the students' records; anti-malware software kept up to date and a firewall would help prevent this. Phishing emails could trick staff into revealing their passwords, so staff training is needed. A brute force attack could guess passwords, so the school should enforce strong passwords and limit the number of login attempts. Data could also be intercepted as it travels across the network, so it should be encrypted.

2. • Technical defences can be very strong
   • But people can be tricked or manipulated
   • For example by phishing or blagging
   • An attacker with valid login details looks like a real user
   • People choose weak passwords or write them down
   • So staff training matters
   Model answer

   Technical defences such as firewalls and encryption can be very strong, but people can be tricked. Social engineering, such as phishing emails or blagging phone calls, persuades someone to hand over their password. Once an attacker has valid credentials, no firewall can stop them, because they look like a legitimate user. People also choose weak passwords and write them down. That is why staff training is so important.

This or That

1. A virus A worm spreads on its own. A virus waits for someone to open its host file.
2. Unreadable The data can still be captured, but without the key it is meaningless.
3. Input validation Checking what users type stops SQL code being run as a query.
4. No: it finds weaknesses to fix Penetration testing reports weaknesses. Fixing them is what stops attacks.
5. The traffic comes from thousands of addresses Blocking one address is easy. Blocking thousands of compromised machines is not.
6. Blagging Blagging invents a scenario to gain trust. Shouldering is watching someone type.
7. Anti-malware software Anti-malware checks files against known signatures. A firewall filters network traffic.
8. A stolen password With two factors, a password alone is not enough to log in.

Memory Match

• A 6 Worm: Spreads by itself across a network
• B 3 Trojan: Malware disguised as useful software
• C 4 Phishing: Fake messages that trick people
• D 5 Brute force: Trying every possible password
• E 1 Firewall: Blocks traffic that breaks its rules
• F 2 Penetration testing: Authorised attacks to find weaknesses

Sort It

1. Strong passwords Common words such as password123 being guessed A strong password avoids dictionary words.
2. Staff training A caller pretending to be from IT support Training teaches staff never to give out passwords.
3. Staff training A phishing email asking staff for their password Trained staff spot fake emails.
4. Strong passwords A brute force attack on an administrator account A strong password, attempt limits and two factor authentication protect it.
5. Input validation Typing ' OR '1'='1 into a login box That is SQL injection: checking input stops it running as code.
6. Strong passwords Software trying millions of password guesses Long, complex passwords and attempt limits defeat brute force.
7. Input validation A web form that runs whatever the user types Every input must be checked before it is used.
8. Encryption Files read from a stolen laptop If the drive is encrypted, the files are useless without the key.
9. Encryption Data intercepted as it travels across a network Encryption does not stop interception, but it makes the data unreadable.
10. Staff training Someone watching a PIN being typed Training teaches people to shield what they type.
11. Encryption Packet sniffing on public Wi-Fi Encrypted traffic is meaningless to whoever captures it.
12. Input validation SQL code entered into a search box Validation and parameterised queries keep data separate from code.