Ubuntu Security Notice USN-6585-1

Ubuntu Security Notice 6585-1 - Fabian Bäumer, Marcus Brinkmann, Joerg Schwenk discovered that the SSH protocol was vulnerable to a prefix truncation attack. If a remote attacker was able to intercept SSH communications, extension negotiation messages could be truncated, possibly leading to certain algorithms and features being downgraded. This issue is known as the Terrapin attack. This update adds protocol extensions to mitigate this issue.

algorithms attack attacker communications extension fabian bäumer features intercept issue marcus marcus brinkmann messages negotiation notice protocol security security notice ssh ssh communications ssh protocol terrapin terrapin attack truncated ubuntu usn vulnerable