Out-of-bounds read of the encoding[] array in fs_read_glyphs() in the
font-server client (src/fc/fserve.c). Debian builds libXfont2 with
--disable-fc (debian/rules), so the font-server client is not compiled:
the shipped libXfont2.so.2.0.0 (1:2.0.6-1+deb13u1) contains no
fs_read_glyphs or other fserve code. Debian rates it unimportant
("Disabled support to connect to font server since 1:1.4.7-1").