VULNERABILITY DETAILS
In the GetFloatCharRectInPixels function in pdf/pdfium/pdfium_page.cc, the return value of FPDFText_GetCharBox is not validated such that stack variables may not be initialised before subsequent use. These values are then returned and may leak into v8 either in the renderer or the plugin engine.

https://chromium.googlesource.com/chromium/src/+/master/pdf/pdfium/pdfium_page.cc#93

Please note that this was found statically using Semmle, as such we do not have a repro case.

VERSION
Chrome Version: 83
Operating System: All

CREDIT INFORMATION
Externally reported security bugs may appear in Chrome release notes. If
this bug is included, how would you like to be credited?
Reporter credit: Gareth Evans (Microsoft)