A heap-based buffer overflow issue was discovered in UPX in PackTmt::pack() in p_tmt.cpp file. The flow allows an attacker to cause a denial of service (abort) via a crafted file.
A Segmentation fault was found in UPX in PackLinuxElf64::invert_pt_dynamic() in p_lx_elf.cpp. An attacker with a crafted input file allows invalid memory address access that could lead to a denial of service.
A flaw was found in upx canPack in p_lx_elf.cpp in UPX 3.96. This flaw allows attackers to cause a denial of service (SEGV or buffer overflow and application crash) or possibly have unspecified other impacts via a crafted ELF. The highest threat from this vulnerability is to system availability.