CVE-2017-1000253
Linux distributions that have not patched their long-term kernels with https://git.kernel.org/linus/a87938b2e246b81b4fb713edb371a9fa3c5c3c86 (committed on April 14, 2015). This kernel vulnerability was fixed in April 2015 by commit a87938b2e246b81b4fb713edb371a9fa3c5c3c86 (backported to Linux 3.10.77 in May 2015), but it was not recognized as a security threat. With CONFIG_ARCH_BINFMT_ELF_RANDOMIZE_PIE enabled, and a normal top-down address allocation strategy, load_elf_binary() will attempt to map a PIE binary into an address range immediately below mm-mmap_base.
Unfortunately, load_elf_ binary() does not take account of the need to allocate sufficient space for the entire binary which means that, while the first PT_LOAD segment is mapped below mm-mmap_base, the subsequent PT_LOAD segment(s) end up being mapped above mm-mmap_base into the are that is supposed to be the "gap" between the stack and the binary.
- Listed on CISA KEV (known exploited in the wild)
- Linked to known ransomware campaigns
- SSVC exploitation status: active
- EPSS ≥ 0.50 - high probability of exploitation in the next 30 days
- EPSS percentile: top 2% of all CVEs by exploitation likelihood
- Public exploit or PoC is available
- CVSS base score ≥ 7.0