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352
A Virtual Machine Introspection Based Architecture for Intrusion Detection
- In Proc. Network and Distributed Systems Security Symposium
, 2003
"... Today's architectures for intrusion detection force the IDS designer to make a difficult choice. If the IDS resides on the host, it has an excellent view of what is happening in that host's software, but is highly susceptible to attack. On the other hand, if the IDS resides in the network, ..."
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Cited by 423 (5 self)
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Today's architectures for intrusion detection force the IDS designer to make a difficult choice. If the IDS resides on the host, it has an excellent view of what is happening in that host's software, but is highly susceptible to attack. On the other hand, if the IDS resides in the network, it is more resistant to attack, but has a poor view of what is happening inside the host, making it more susceptible to evasion. In this paper we present an architecture that retains the visibility of a host-based IDS, but pulls the IDS outside of the host for greater attack resistance. We achieve this through the use of a virtual machine monitor. Using this approach allows us to isolate the IDS from the monitored host but still retain excellent visibility into the host's state. The VMM also offers us the unique ability to completely mediate interactions between the host software and the underlying hardware. We present a detailed study of our architecture, including Livewire, a prototype implementation. We demonstrate Livewire by implementing a suite of simple intrusion detection policies and using them to detect real attacks.
Improving Host Security with System Call Policies
- In Proceedings of the 12th Usenix Security Symposium
, 2002
"... We introduce a system that eliminates the need to run programs in privileged process contexts. Using our system, programs run unprivileged but may execute certain operations with elevated privileges as determined by a configurable policy eliminating the need for suid or sgid binaries. We present the ..."
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Cited by 330 (0 self)
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We introduce a system that eliminates the need to run programs in privileged process contexts. Using our system, programs run unprivileged but may execute certain operations with elevated privileges as determined by a configurable policy eliminating the need for suid or sgid binaries. We present the design and analysis of the "Systrace" facility which supports fine grained process confinement, intrusion detection, auditing and privilege elevation. It also facilitates the often difficult process of policy generation. With Systrace, it is possible to generate policies automatically in a training session or generate them interactively during program execution. The policies describe the desired behavior of services or user applications on a system call level and are enforced to prevent operations that are not explicitly permitted. We show that Systrace is efficient and does not impose significant performance penalties.
Computer Immunology
- Communications of the ACM
, 1996
"... Natural immune systems protect animals from dangerous foreign pathogens, including bacteria, viruses, parasites, and toxins. Their role in the body is analogous to that of computer security systems in computing. Although there are many differences between living organisms and computer systems, this ..."
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Cited by 226 (8 self)
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Natural immune systems protect animals from dangerous foreign pathogens, including bacteria, viruses, parasites, and toxins. Their role in the body is analogous to that of computer security systems in computing. Although there are many differences between living organisms and computer systems, this article argues that the similarities are compelling and could point the way to improved computer security. Improvements can be achieved by designing computer immune systems that have some of the important properties illustrated by natural immune systems. These include multi-layered protection, highly distributed detection and memory systems, diversity of detection ability across individuals, inexact matching strategies, and sensitivity to most new foreign patterns. We first give an overview of how the immune system relates to computer security. We then illustrate these ideas with two examples.
Mimicry Attacks on Host-Based Intrusion Detection Systems
- In Proceedings of the 9th ACM Conference on Computer and Communications Security
, 2002
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The essence of command injection attacks in web applications
, 2006
"... Web applications typically interact with a back-end database to retrieve persistent data and then present the data to the user as dynamically generated output, such as HTML web pages. However, this interaction is commonly done through a low-level API by dynamically constructing query strings within ..."
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Cited by 185 (5 self)
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Web applications typically interact with a back-end database to retrieve persistent data and then present the data to the user as dynamically generated output, such as HTML web pages. However, this interaction is commonly done through a low-level API by dynamically constructing query strings within a general-purpose programming language, such as Java. This low-level interaction is ad hoc because it does not take into account the structure of the output language. Accordingly, user inputs are treated as isolated lexical entities which, if not properly sanitized, can cause the web application to generate unintended output. This is called a command injection attack, which poses a serious threat to web application security. This paper presents the first formal definition of command injection attacks in the context of web applications, and gives a sound and complete algorithm for preventing them based on context-free grammars and compiler parsing techniques. Our key observation is that, for an attack to succeed, the input that gets propagated into the database query or the output document must change the intended syntactic structure of the query or document. Our definition and algorithm are general and apply to many forms of command injection attacks. We validate our approach with SQLCHECK, an implementation for the setting of SQL command injection attacks. We evaluated SQLCHECK on real-world web applications with systematically compiled real-world attack data as input. SQLCHECK produced no false positives or false negatives, incurred low runtime overhead, and applied straightforwardly to web applications written in different languages.
Non-control-data attacks are realistic threats
- In USENIX Security Symposium
, 2005
"... Most memory corruption attacks and Internet worms follow a familiar pattern known as the control-data attack. Hence, many defensive techniques are designed to protect program control flow integrity. Although earlier work did suggest the existence of attacks that do not alter control flow, such attac ..."
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Cited by 185 (6 self)
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Most memory corruption attacks and Internet worms follow a familiar pattern known as the control-data attack. Hence, many defensive techniques are designed to protect program control flow integrity. Although earlier work did suggest the existence of attacks that do not alter control flow, such attacks are generally believed to be rare against real-world software. The key contribution of this paper is to show that non-control-data attacks are realistic. We demonstrate that many real-world applications, including FTP, SSH, Telnet, and HTTP servers, are vulnerable to such attacks. In each case, the generated attack results in a security compromise equivalent to that due to the controldata attack exploiting the same security bug. Non-control-data attacks corrupt a variety of application data including user identity data, configuration data, user input data, and decision-making data. The success of these attacks and the variety of applications and target data suggest that potential attack patterns are diverse. Attackers are currently focused on control-data attacks, but it is clear that when control flow protection techniques shut them down, they have incentives to study and employ non-control-data attacks. This paper emphasizes the importance of future research efforts to address this realistic threat. 1
Anomaly detection using call stack information
- In IEEE Symposium on Security and Privacy
, 2003
"... The call stack of a program execution can be a very good information source for intrusion detection. There is no prior work on dynamically extracting information from call stack and effectively using it to detect exploits. In this paper, we propose a new method to do anomaly detection using call sta ..."
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Cited by 174 (6 self)
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The call stack of a program execution can be a very good information source for intrusion detection. There is no prior work on dynamically extracting information from call stack and effectively using it to detect exploits. In this paper, we propose a new method to do anomaly detection using call stack information. The basic idea is to extract return ad-dresses from the call stack, and generate abstract execu-tion path between two program execution points. Experi-ments show that our method can detect some attacks that cannot be detected by other approaches, while its conver-gence and false positive performance is comparable to or better than the other approaches. We compare our method with other approaches by analyzing their underlying prin-ciples and thus achieve a better characterization of their performance, in particular, on what and why attacks will be missed by the various approaches. 1
Using Programmer-Written Compiler Extensions to Catch Security Holes
"... This paper shows how system-specific static analysis can nd security errors that violate rules such as "integers from untrusted sources must be sanitized before use" and "do not dereference user-supplied pointers." In our approach, programmers write system-specific extensions tha ..."
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Cited by 171 (6 self)
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This paper shows how system-specific static analysis can nd security errors that violate rules such as "integers from untrusted sources must be sanitized before use" and "do not dereference user-supplied pointers." In our approach, programmers write system-specific extensions that are linked into the compiler and check their code for errors. We demonstrate the approach's effectiveness by using it to nd over 100 security errors in Linux and OpenBSD, over 50 of which have led to kernel patches. An unusual feature ofour approach is the use of methods to automatically detect when we miss code actions that should be checked.
Flashback: A Lightweight Extension for Rollback and Deterministic Replay for Software Debugging
- In USENIX Annual Technical Conference, General Track
, 2004
"... Unfortunately, finding software bugs is a very challenging task because many bugs are hard to reproduce. While debugging a program, it would be very useful to rollback a crashed program to a previous execution point and deterministically re-execute the "buggy " code region. However ..."
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Cited by 155 (7 self)
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Unfortunately, finding software bugs is a very challenging task because many bugs are hard to reproduce. While debugging a program, it would be very useful to rollback a crashed program to a previous execution point and deterministically re-execute the "buggy " code region. However, most previous work on rollback and replay support was designed to survive hardware or operating system failures, and is therefore too heavyweight for the fine-grained rollback and replay needed for software debugging. This paper presents Flashback, a lightweight OS extension that provides fine-grained rollback and replay to help debug software. Flashback uses shadow processes to efficiently roll back in-memory state of a process, and logs a process ' interactions with the system to support deterministic replay. Both shadow processes and logging of system calls are implemented in a lightweight fashion specifically designed for the purpose of software debugging. We have implemented a prototype of Flashback in the Linux operating system. Our experimental results with micro-benchmarks and real applications show that Flashback adds little overhead and can quickly roll back a debugged program to a previous execution point and deterministically replay from that point.
Static Analysis of Executables to Detect Malicious Patterns
- In Proceedings of the 12th USENIX Security Symposium
, 2003
"... Malicious code detection is a crucial component of any defense mechanism. In this paper, we present a unique viewpoint on malicious code detection. We regard malicious code detection as an obfuscation-deobfuscation game between malicious code writers and researchers working on malicious code detecti ..."
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Cited by 149 (0 self)
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Malicious code detection is a crucial component of any defense mechanism. In this paper, we present a unique viewpoint on malicious code detection. We regard malicious code detection as an obfuscation-deobfuscation game between malicious code writers and researchers working on malicious code detection. Malicious code writers attempt to obfuscate the malicious code to subvert the malicious code detectors, such as anti-virus software. We tested the resilience of three commercial virus scanners against code-obfuscation attacks. The results were surprising: the three commercial virus scanners could be subverted by very simple obfuscation transformations! We present an architecture for detecting malicious patterns in executables that is resilient to common obfuscation transformations. Experimental results demonstrate the efficacy of our prototype tool, SAFE (a static analyzer for executables). 1
