The *_get_synthetic_symtab functions in the Binary File Descriptor (BFD) library (aka libbfd), as distributed in GNU Binutils 2.29, do not ensure a unique PLT entry for a symbol, which allows remote attackers to cause a denial of service (heap-based buffer overflow and application crash) or possibly have unspecified other impact via a crafted ELF file, related to elf32-i386.c and elf64-x86-64.c.