Ubuntu Security Notice USN-4196-1

Ubuntu Security Notice 4196-1 - It was discovered that python-ecdsa incorrectly handled certain signatures. A remote attacker could possibly use this issue to cause python-ecdsa to generate unexpected exceptions, resulting in a denial of service. It was discovered that python-ecdsa incorrectly verified DER encoding in signatures. A remote attacker could use this issue to perform certain malleability attacks. Various other issues were also addressed.