Application layer blocker for preventing on cyber security

Application layer blocker for preventing on cyber security

Abstract:-

This project propose SigFree, a realtime, signature-free, out-ofthe-box, application layer blocker for preventing buffer overflow attacks, one of the most serious cyber security threats. SigFree can filter out code-injection buffer overflow attack messages targeting at various Internet services such as web service. Motivated by the observation that buffer overflow attacks typically contain executables whereas legitimate client requests never contain executables in most Internet services, SigFree blocks attacks by detecting the presence of code. SigFree first blindly dissembles and extracts instruction sequences from a request. It then applies a novel technique called code abstraction, which uses data flow anomaly to prune useless instructions in an instruction sequence. Finally it compares the number of useful instructions to a threshold to determine if this instruction sequence contains code. SigFree is signature free, thus it can block new and unknown buffer overflow attacks; SigFree is also immunized from most attack-side code obfuscation methods. Since SigFree is transparent to the servers being protected, it is good for economical Internet wide deployment with very low deployment and maintenance cost. We implemented and tested SigFree; our experimental study showed that SigFree could block all types of codeinjection attack packets (above 250) tested in our experiments. Moreover, SigFree causes negligible throughput degradation to normal client requests

Existence System:-

Detection of Data Flow Anomalies There are static or dynamic methods to detect data flow anomalies in the software reliability and testing field. Static methods are not suitable in our case due to its slow speed; dynamic methods are not suitable either due to the need for real execution of a program with some inputs.

Proposed System:-

Their scheme is rule-based, whereas SigFree is a generic approach which does not require any pre-known patterns. Then, it uses the found patterns and a data flow analysis technique called program slicing to analyze the packet’s payload to see if the packet really contains code Four rules (or cases) are discussed in their project: Case 1 not only assumes the occurrence of the call/jmp instructions, but also expects the push instruction appears before the branch; Case 2 relies on the interrupt instruction; Case 3 relies on instruction ret; Case 4 exploits hidden branch instructions. Besides, they used a special rule to detect polymorphic exploit code which contains a loop. Although they mentioned that the above rules are initial sets and may require updating with time, it is always possible for attackers to bypass those pre-known rules. Moreover, more rules mean more overhead and longer latency in filtering packets. In contrast, SigFree exploits a different data flow analysis technique, which is much harder for exploit code to evade.

We proposed SigFree, a realtime, signature free, out of- the-box blocker that can filter code-injection buffer overflow attack messages, one of the most serious cyber security threats, to various Internet services. SigFree does not require any signatures, thus it can block new, unknown attacks.

We have implemented a SigFree prototype as a proxy to protect web servers. Our empirical study shows that there exists clean-cut “boundaries” between code embedded payloads and data payloads when our codedata separation criteria are applied. We have identified the “boundaries” (or thresholds) and been able to detect/ block all 50 attack packets generated by Metasploitframework , all 200 polymorphic shellcode packets generated by two well-known polymorphic shellcode engine ADMmutate and CLET , and worm Slammer, CodeRed and a CodeRed variation, when they are well mixed with various types of data packets. Also, our experiment results show that the throughput degradation caused by SigFree is negligible.

Hardware Requirements:

• System : Pentium IV 2.4 GHz.
• Hard Disk : 40 GB.
• Floppy Drive : 1.44 Mb.
• Monitor : 15 VGA Colour.
• Mouse : Logitech.
• Ram : 512 Mb.

Software Requirements:-

Language: Java / Dot Net

OS: Windows XP

Comments are closed.