alt Hacker NewsWilling to bet that a default "treat PDFs/documents/spreadsheets as dumb" option in operating systems would eliminate the majority of common one-click vulnerabilies out there. And exactly 0.001% of actual use cases would be affected.
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PDFs are just absurdly complicated in general. Dumbing down the parser might be the right idea. I wonder what consequences that would have with how intertwined PostScript and PDF in general are with macOS/iOS; maybe that's why the PostScript engine was removed with macOS Sonoma/iOS 17? I don't know if that was only user facing behavior and Apple is still working to remove the internal usages.
No. Very few PDF exploits come from the officially sanctioned way of running code (JavaScript) inside PDF. Most are just plain old parser bugs.
That's kind of what Adobe does with downloaded PDFs, you have to click the Enable button to turn on more document features. My schematic capture app will output a PDF that has links that will take you to specific spots on a page and also some JavaScript where you can right click on a part and see it's BOM information. None of that stuff works until you click the Enable button. I've also seen some vendors offer not only normal 3D model files and 2D drawings but a PDF that has an interactive 3D model inside. It's kinda cool how much random shit can go into a PDF but it's clearly a massive malware vector.
One neat thing I've seen is a PDF that will ping an IP catcher when opened in Adobe, regardless of the security level. The same can be done with word docs, excel spreadsheets, and even SVGs.
Did we do that with Excel spreadsheets so that macros are disabled by default?
"dumb" isn't a real thing in computer science though. You mean render them to bitmaps in a sandbox?
This is one of the things iOS's Lockdown Mode does. I wish the features of Lockdown Mode were able to be enabled individually instead of a single all or none option.
https://support.apple.com/en-us/105120