fix(cmap): bounds-check ArrayOfHexStrings index in bfrange lookup#478
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J-F-Liu merged 1 commit intoJ-F-Liu:mainfrom Mar 14, 2026
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Summary
Malformed
CMapbfrange entries can declare a source code range larger than their ArrayOfHexStrings array (e.g., range covers 5 codes but array has only 2 entries). WhenToUnicodeCMap::get()looks up a code that falls past the end of the array, it panics with an index out of bounds.Fix
Added a bounds check on the array index in the
ArrayOfHexStringsmatch arm. When the index exceeds the array length, return U+FFFD (replacement character) instead of panicking. This is consistent withget_or_replacement_char(), which already uses U+FFFD as the fallback for missing mappings. The actual mapped entries are still returned correctly.