The Pallets Project flask version Before 0.12.3 contains a CWE-20: Improper
Input Validation vulnerability in flask that can result in Large amount of
memory usage possibly leading to denial of service. This attack appear to
be exploitable via Attacker provides JSON data in incorrect encoding. This
vulnerability appears to have been fixed in 0.12.3. NOTE: this may overlap
CVE-2019-1010083.

leosilva