Fuzz testing has been gaining ground recently with substantial efforts devoted to the area. Typically, fuzzers take a set of seed inputs and leverage random mutations to continually improve the inputs with respect to a cost, e.g. program code coverage, to discover vulnerabilities or bugs. Following this methodology, fuzzers are very good at generating unstructured inputs that achieve high coverage. However fuzzers are less effective when the inputs are structured, say they conform to an input grammar. Due to the nature of random mutations, the overwhelming abundance of inputs generated by this common fuzzing practice often adversely hinders the effectiveness and efficiency of fuzzers on grammar-aware applications. The problem of testing becomes even harder, when the goal is not only to achieve increased code coverage, but also to nd complex vulnerabilities related to other cost measures, say high resource consumption in an application.
We propose Saffron an adaptive grammar-based fuzzing approach to effectively and efficiently generate inputs that expose expensive executions in programs. Saffron takes as input a user-provided grammar, which describes the input space of the program under analysis, and uses it to generate test inputs. Saffron assumes that the grammar description is approximate since precisely describing the input program space is often difficult as a program may accept unintended inputs due to e.g., errors in parsing. Yet these inputs may reveal worst-case complexity vulnerabilities. The novelty of Saffron is then twofold: (1) Given the user-provided grammar, Saffron attempts to discover whether the program accepts unexpected inputs outside of the provided grammar, and if so, it repairs the grammar via grammar mutations. The repaired grammar serves as a specification of the actual inputs accepted by the application. (2) Based on the refined grammar, it generates concrete test inputs. It starts by treating every production rule in the grammar with equal probability of being used for generating concrete inputs. It then adaptively refines the probabilities along the way by increasing the probabilities for rules that have been used to generate inputs that improve a cost, e.g., code coverage or arbitrary user-defined cost. Evaluation results show that Saffron significantly outperforms state-of-the-art baselines.
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From Quantum Fuzzing to the Multiverse: Possible Effective Uses of Quantum Noise
Quantum noise is seen by many researchers as a problem to be resolved. Current solutions increase quantum computing system costs significantly by requiring numerous hardware qubits to represent a logical qubit to average the noise away. However, despite its deleterious effects on system performance and the increased costs it creates, it may have some potential uses. This paper evaluates those. Specifically, it considers how quantum noise could be used to support the fuzzing cybersecurity and testing technique and AI techniques such as certain swarm artificial intelligence algorithms. Fuzzing is used to identify vulnerabilities in software by generating massive amounts of input cases for a program. Quantum noise provides an effective built-in fuzzing capability that is centered around the actual answer to a computation. These same phenomena, of clustered and centered fuzz-noise around the answer of an operation, could be similarly useful to AI techniques that can make effective use of lots of point values for optimization. Effectively, by concurrently considering the ‘multiverse’ of possible results to an operation, created by compounding noise, more beneficial solutions that are proximal to the actual result of an operation can be identified via testing quantum noise points with an effectiveness algorithm. Both of these potential uses for quantum noise are considered herein.
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- Award ID(s):
- 1757659
- NSF-PAR ID:
- 10318775
- Editor(s):
- Arai, Kohei
- Date Published:
- Journal Name:
- Advances in Information and Communication. FICC 2022
- Issue:
- 2022
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1007/978-3-030-98012-2_30
