CVE-2026-59679 fs_read_glyphs() heap OOB read/write via encoding array index mismatch in libXfont2

fsreadglyphs in the libXfont2 font-server client src/fc/fserve.c indexes the per-character encoding array using numchars from the FSQueryXBitmaps16 reply, but that array was allocated with a size derived from numextents in the separate FSQueryXExtents16 reply. The two CARD32 fields are never...