The r_read_* functions in libr/include/r_endian.h in radare2 1.2.1 allow remote attackers to cause a denial of service (NULL pointer dereference and application crash) via a crafted binary file, as demonstrated by the r_read_le32 function.
https://github.com/radare/radare2/issues/6816
https://github.com/radare/radare2/commit/1ea23bd6040441a21fbcfba69dce9a01af03f989