F1 F2 F3 F4 F5 F6 Full [new]: Cidfont

These names appear when a PDF file is created by software (like Adobe InDesign or Illustrator) that uses CID (Character ID) keyed fonts

cpdf -replace-fonts "CIDFont+F2" "NotoSansCJKjp-Bold" in.pdf -o out.pdf cidfont f1 f2 f3 f4 f5 f6 full

Go to File > Properties (or press Ctrl+D ) and click the Fonts tab. These names appear when a PDF file is

CIDFonts were developed by Adobe to overcome the limitations of older font technologies, which struggled with scripts containing thousands of glyphs. Within the CID-keyed font architecture, a unique classification system exists: . : Your computer lacks the original font family

: Your computer lacks the original font family (often common ones like Arial or Helvetica ) that the PDF is trying to reference.

Use the "Preflight" menu in Acrobat Pro to "Embed fonts even if text is invisible". This can sometimes repair the broken connection between the label and the actual font data. For the Creators: How to Prevent This