Common cyber attacks
Introduction
Every 39 seconds oru cyber attack nadakkudhu worldwide! š± 2025 la India la mattum 15 lakh+ cyber crime cases report aachi.
Hackers epdhi attack pannuranga, enna type of attacks use pannuranga ā idhellam therinjha dhaan namma defend panna mudiyum.
Indha article la common cyber attacks, real-world examples, and prevention techniques ā ellam detailed ah paapom! š”ļø
Phishing Attacks š£
Phishing = Fake messages/emails anuppi sensitive info steal pannuradhu.
Types of Phishing:
| Type | Description | Example |
|---|---|---|
| **Email Phishing** | Mass fake emails | "Your SBI account suspended, click here" |
| **Spear Phishing** | Targeted attack on specific person | CEO ku fake vendor invoice |
| **Smishing** | SMS phishing | "KYC update pannunga" SMS with link |
| **Vishing** | Voice call phishing | Fake bank call asking OTP |
| **Whaling** | Targeting top executives | CFO ku urgent wire transfer request |
How to identify:
- Urgency create pannum ā "Act NOW or account blocked!"
- Spelling mistakes, weird email addresses
- Suspicious links (hover panni paanga before clicking)
- Asking for passwords, OTP, personal info
Malware ā The Digital Virus š¦
Malware = Malicious Software. Different types irukku:
š¦ Virus ā Attaches to files, spreads when file opened
š Worm ā Self-replicating, spreads through network automatically
š“ Trojan ā Looks legitimate but has hidden malicious code
š Ransomware ā Encrypts files, demands ransom payment
šļø Spyware ā Secretly monitors your activity
āØļø Keylogger ā Records every keystroke (passwords capture)
š¤ Botnet ā Infected computers controlled remotely
Real Example: WannaCry Ransomware (2017)
- 2,30,000+ computers in 150 countries affected
- NHS hospitals in UK shut down
- Demanded $300 Bitcoin ransom
- Damage: $4 billion+ worldwide! šø
Real Scenario: AIIMS Ransomware Attack
š„ November 2022 ā AIIMS Delhi Ransomware Attack
India's premier hospital AIIMS Delhi got hit by ransomware:
- 40 million+ patient records compromised
- Hospital systems down for 2 weeks
- Doctors went back to pen and paper
- Hackers demanded ā¹200 crore in crypto
- OPD, emergency, lab services ā all affected
Impact: Patient care delayed, surgeries rescheduled, data at risk.
Lesson: Even critical infrastructure is vulnerable. Backups, segmentation, and security training ā essential! š”ļø
DDoS Attacks š
DDoS = Distributed Denial of Service
Imagine oru small chai shop ku suddenly 10,000 people varudhu. Shop handle panna mudiyaadhu, genuine customers ku service kedaikkaadhu. Same concept online la! ā
How DDoS works:
- Hacker controls thousands of compromised computers (botnet)
- All computers simultaneously send requests to target server
- Server overwhelmed ā crashes ā legitimate users can't access
| DDoS Type | Layer | Method |
|---|---|---|
| Volume-based | Network | UDP flood, ICMP flood |
| Protocol | Transport | SYN flood, Ping of Death |
| Application | Application | HTTP flood, Slowloris |
Real Example: GitHub (2018) ā 1.35 Tbps DDoS attack, largest ever at that time. Mitigated within 10 minutes using Akamai! š
SQL Injection š
SQL Injection = Website database la unauthorized commands execute pannuradhu.
Oru login form la username field la instead of normal input:
Idhu database ku solludhu ā "always true" ā login without password! š±
Prevention:
- Input validation ā user input sanitize pannunga
- Parameterized queries use pannunga
- ORM (Object Relational Mapping) use pannunga
- Least privilege ā database user ku minimum permissions
Impact: Yahoo (2013) ā 3 billion accounts breached, partly through SQL injection! Largest data breach in history. š
Man-in-the-Middle Attack šµļø
MITM = Hacker un communication middle la eavesdrop pannuradhu.
Nee āāā¶ [HACKER] āāā¶ Bank Website
Nee bank website ku data anuppuva. Hacker middle la intercept panni:
- Un login credentials paappaan
- Data modify pannuvaan
- Fake responses anuppuvaan
Common scenarios:
- Public WiFi (coffee shop, airport) ā most vulnerable!
- Fake WiFi hotspot ā "Free_Airport_WiFi"
- HTTP websites (no HTTPS)
- Compromised routers
Prevention:
- HTTPS websites mattum use pannunga š
- Public WiFi la VPN use pannunga
- Free WiFi ah trust pannaadheenga
- Certificate warnings ignore pannaadheenga
Attack Kill Chain
āāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāā ā CYBER ATTACK KILL CHAIN ā āāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāā⤠ā ā ā 1. RECONNAISSANCE āāā¶ Target info gathering ā ā ā (social media, DNS) ā ā ā¼ ā ā 2. WEAPONIZATION āāā¶ Create attack payload ā ā ā (malware, exploit) ā ā ā¼ ā ā 3. DELIVERY āāāāāāāāā¶ Send to target ā ā ā (email, USB, web) ā ā ā¼ ā ā 4. EXPLOITATION āāāāā¶ Trigger vulnerability ā ā ā (code execution) ā ā ā¼ ā ā 5. INSTALLATION āāāāā¶ Install backdoor ā ā ā (persistent access) ā ā ā¼ ā ā 6. COMMAND & CTRL āāā¶ Remote control ā ā ā (C2 server) ā ā ā¼ ā ā 7. ACTIONS āāāāāāāāāā¶ Achieve objective ā ā (data theft, damage) ā ā ā ā š”ļø DEFEND at EVERY stage to break the chain! ā ā ā āāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāāā
Zero-Day & Advanced Attacks
Advanced attacks romba dangerous:
š Zero-Day Attack
- Software la unknown vulnerability exploit
- Patch available aagura munnadhi attack
- "Zero days" to fix ā adhaan name
- Very expensive in black market ($100K - $2.5M)
š Supply Chain Attack
- Software vendor ah compromise panni, updates through malware spread
- SolarWinds (2020) ā 18,000 organizations affected including US government!
šÆ APT (Advanced Persistent Threat)
- Nation-state level hackers
- Months/years target system la hidden ah iruppanga
- Goal: Espionage, data theft, sabotage
š° Cryptojacking
- Un computer secretly use panni cryptocurrency mine pannuradhu
- Computer slow aagum, electricity bill increase aagum
- Website visit panna kuda nadakkum (browser mining)
Prevention Best Practices
Ivanga follow pannunga ā most attacks prevent pannalam:
š Authentication: Strong passwords + 2FA everywhere
š§ Email Safety: Unknown links click pannaadheenga, attachments open pannaadheenga
š Updates: OS, software, apps ā immediately update pannunga
š¾ Backups: 3-2-1 rule ā 3 copies, 2 different media, 1 offsite
š Network: VPN use pannunga, public WiFi avoid pannunga
š Awareness: Latest threats pathi read pannunga
š Verify: Unknown calls/emails la always verify the source
š”ļø Antivirus: Reputed antivirus install and update pannunga
Attack Comparison Table
All attacks oru comparison la:
| Attack | Difficulty | Impact | Prevention |
|---|---|---|---|
| Phishing | Easy | High | Awareness, 2FA |
| Malware | Medium | High | Antivirus, Updates |
| DDoS | Medium | Medium | CDN, Rate limiting |
| SQL Injection | Medium | Critical | Input validation |
| Social Engineering | Easy | High | Training |
| MITM | Medium | High | HTTPS, VPN |
| Zero-Day | Hard | Critical | Patch management |
| Ransomware | Medium | Critical | Backups, Segmentation |
Key insight: Most successful attacks exploit human weakness, not technical weakness! 80% of breaches involve human element. š§
ā Summary & Key Takeaways
What we learned:
ā Phishing = Fake messages to steal credentials (most common!)
ā Malware = Virus, ransomware, trojan, spyware
ā DDoS = Overwhelming servers with fake traffic
ā SQL Injection = Attacking databases through web inputs
ā Social Engineering = Manipulating humans, not machines
ā MITM = Intercepting communications
ā Kill Chain = 7-step attack lifecycle
Key takeaway: 80% of attacks exploit human errors. Awareness is your strongest defense! š§
Next article: "IAM Basics" ā Identity and Access Management, controlling who can access what! š
š Mini Challenge
Challenge: Phishing Email Analysis Lab
Oru week time la phishing detection skills improve pannunga:
- Identify Phishing Emails ā Namma spam folder la 10 emails paapom. Each email analyze pannunga: sender address check, suspicious links verify, grammar errors identify, urgency language detect.
- Wireshark MITM Demo ā Kali Linux la Wireshark install pannunga. ARP spoofing lab follow pannunga (TryHackMe MITM room). Nee epdhi man-in-the-middle attack work panunga visualize pannunga.
- SQL Injection Practice ā DVWA (Damn Vulnerable Web App) setup pannunga. SQL injection vulnerable login form la try pannunga (
admin' OR '1'='1). Prevention techniques understand pannunga.
- Social Engineering Audit ā Un organization la 5 people call pannunga (permission take panni). Pretexting scenario use pannunga. "I'm from IT, your password reset pannanum, current password sollanunga?" ā how many fall for this? Results document pannunga.
- Malware Analysis Sandbox ā Any malware sample (safe, isolated lab la) Wireshark + Process Monitor use panni analyze pannunga. Network traffic paappom, registry changes paappom, file system modifications paappom.
Indha challenge complete pannidha, nee attack patterns recognize panna master! šÆ
Interview Questions
Q1: What is the most common attack? How to prevent?
A: Phishing ā 90% of breaches phishing through start aagudhu. Prevention: user awareness training, email filtering, 2FA, link verification.
Q2: Explain ransomware attack and recovery strategy.
A: Attacker data encrypt panni ransom demand pannum. Recovery: regular backups (3-2-1 rule), offline backups, segmentation, incident response plan. Ransom pay pannaadheenga ā guarantee illa.
Q3: DDoS attack epdhi work panunga?
A: Thousands of compromised computers (botnet) server attack panni overwhelm pannunga. Server crash aagum, legitimate users access mudiyaadhu. Mitigation: rate limiting, CDN, DDoS protection service, traffic filtering.
Q4: SQL Injection vulnerability epdhi prevent pannuradhu?
A: Input validation (user input sanitize), parameterized queries, ORM usage, principle of least privilege (database user permissions limit), WAF (Web Application Firewall).
Q5: Social Engineering attack la company defend panna strategy?
A: Regular security awareness training, clear authentication procedures (verify requests), physical security controls, incident reporting culture (people comfortable reporting suspicious activity), executive-level security buy-in.
Frequently Asked Questions
WannaCry attack is an example of what type of malware?
Social Engineering š
Social Engineering = Technology attack illa ā people ah manipulate pannuradhu.
Human psychology exploit pannuranga:
š Pretexting ā Fake identity create panni trust gain pannuradhu
"I'm from IT department, your password expired, tell me your current password"
š¬ Baiting ā Tempting offer through trap pannuradhu
Parking lot la "Salary Details" labeled USB drive pottu vaikka ā curiosity la plug panniduvanga
š Quid Pro Quo ā Something for something
"Free antivirus install pannren, just give me remote access"
šŖ Tailgating ā Physically following authorized person into restricted area
Kevin Mitnick ā world's most famous social engineer. FBI's most wanted hacker. His weapon? Not code ā conversation! š£ļø