[debian-mysql] Bug#788895: mysql-5.5: defaults to 512-bit FFDHE; should be at least 2048-bit FFDHE

[Daniel Kahn Gillmor]

Source: mysql-5.5
Version: 5.1.73-1
Severity: important
Tags: upstream patch
Control: forwarded -1 http://bugs.mysql.com/bug.php?id=77275

all existing versions of MySQL present a 512-bit modulus when
negotiating a Finite-Field Diffie-Hellman Ephemeral (FFDHE) handshake
in TLS.  This is grossly negligent (see https://weakdh.org)

Upstream's bug fix (complete with novel Finite Field DHE group, whose
structure i have not yet examined) is here:

https://github.com/mysql/mysql-server/commit/866b988a76e8e7e217017a7883a52a12ec5024b9

This (or something like it, using a well-analyzed group) should
probably be applied to all supported versions of MySQL.

     --dkg

-- System Information:
Debian Release: stretch/sid
  APT prefers testing
  APT policy: (500, 'testing'), (200, 'unstable'), (1, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 4.0.0-1-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)