What created the file or where did you download it?
Traditional PostScript fonts (Type 1) were limited to 256 glyphs. This worked for Latin alphabets but was a disaster for East Asian languages like Chinese, Japanese, or Korean (CJK), which require thousands (often tens of thousands) of characters.
Click to save a flattened, freshly encoded version of the file. Method 2: Force Font Substitution in Adobe Acrobat