3 ms·
> Most of the CoreGraphics PDF decoder appears to be Apple proprietary code, but the JBIG2 implementation is from Xpdf, the source code for which is freely avai
by herodotus 5y ago
> Most of the CoreGraphics PDF decoder appears to be Apple proprietary code, but the JBIG2 implementation is from Xpdf, the source code for which is freely available.
When I worked at Apple, we encountered a Jailbreak exploit that relied on some poor code in one of the open-source type fonts. It appeared that someone committed a mod to the project that neglected to do an array bounds check, waited ONE YEAR!!! and then exploited the vulnerability to create a PDF document that would jailbreak a phone if the PDF was viewed.
I guess it is possible that something similar was done here.