Fuzzing Closed-Source Java Script Engines with Coverage Feedback
Summary: Google Project Zero's Ivan Fratric combined the Fuzzilli JavaScript engine fuzzer with the TinyInst dynamic instrumentation library, and added grammar-based mutation support to his black-box binary fuzzer Jackalope, to fuzz closed-source JavaScript engines. The two approaches so far found three security issues in jscript9.dll, the default JavaScript engine used by Internet Explorer.
Bottom line: Internet Explorer is still heavily exploited by real-world attackers, with two IE 0days exploited in the wild in 2020 and three in 2021 so far, one of them in the jscript9 JIT compiler.
Read the original at Google Project Zero ↗
- Topics
- Vulnerabilities & Patching
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