The internet has lots of threats in its Pandora box ranging from malware and identity theft to blackmail and other breaches. One of the most common threats in most networks is the Denial of Service (DoS) attacks. As the name suggests, DoS attacks do the same thing, make resources inaccessible to legitimate users. While at it, malicious actors can propagate further attacks by injecting malware into various systems. Like other many cyber-attacks, DoS attacks usually focus on big giant companies. But with the ‘bring your own device’ rule in most companies, you won’t know when you will fall into their snare. In this case, you will also be the victim.
過去，DoS 攻擊已經演變為分散式 DoS 攻擊，其識別起來更加複雜和複雜。
拒絕服務攻擊簡言之
Besides making resources unavailable to users, DoS attacks usually result in system crashes and slowdowns. If crashing doesn’t happen, DoS attacks flood the services (making them slow down). Crash attacks occur when malicious criminals use bugs to exploit vulnerabilities in a system. Eventually, the system will be overwhelmed, and it will crash. This type of DoS attacks is less common.
The major common type of DoS attacks are the flooding attacks. Flooding attacks occur when malicious actors overwhelm a particular system with large amounts of traffic that the system isn’t able to handle. The system eventually slows down or crashes. Flooding DoS attacks include Ping flood and Ping of Death. These attacks take advantage of the Internet Control Message Protocol (ICMP).
平洪水攻擊
This type of DoS attack occurs when a malicious actor overwhelms the target system with packets of information. At times, they can be malicious and take advantage of vulnerabilities in misconfigured devices.
工作原理
- 在這種攻擊中，惡意行為者盡可能快地發送大量 ping 數據包，而無需等待受害系統回復（泛洪）。
- For this attack to be executed successfully, the malicious actor should have more bandwidth than the victim. When the victim’s system starts to respond to the packets, it will take as much as twice the bandwidth the attacker used to send the packets.
- 帶寬越慢，成功的機會就越大，因為系統將顯著減慢嘗試回應泛洪數據包的速度。
死亡之平 （PoD）
如果泛洪不起作用，攻擊者可能會選擇使用PoD攻擊。在 PoD 中，惡意行為者發送帶有惡意數據包的超大 ping 命令。
工作原理
- Most systems rely on the Internet protocol to communicate over the internet. This protocol usually doesn’t allow packets larger than 65,535 bytes. In these attacks, a malicious actor sends packets larger than the maximum size, and the systems can’t deal with them. As a result, they crash and services are disrupted.
- Malicious actors usually send the larger malformed packets in fragments in their transmission. The receiving system will then start to assemble them, but they will become too larger and cause a buffer overflow. (Buffers store some data for a short period).
- 如果緩衝區溢出，系統可能會崩潰，而惡意行為者正是在這一刻向系統注入惡意軟體。
如何防止平洪水和平死亡攻擊
- 配置防火牆
For general users, a firewall is the first option to consider. A firewall prevents unauthorized access to your system. When appropriately configured, a firewall can block malicious actors from perpetrating DoS attacks.
- 安裝防病毒/反惡意軟體
Reputable up-to-date antimalware and antivirus software can protect you against malicious codes injected by cybercriminals when DoS attacks occur. As a bonus, reputable antimalware/antivirus software has a firewall.
- 更新您的系統
系統更新為與 DoS 攻擊相關的各種漏洞和威脅提供修補程式和修復。使用最新系統可確保您不會成為 DoS 攻擊的受害者。
- 使用 VPN – IPBurger
To perform DoS attacks, a malicious actor needs to know the victim’s IP address. Since a VPN masks your real IP address and replaces it with a virtual IP address, you will be safe from these attacks.
