CVE-2020-8955: backport 2.7.1 CVEs to 20.04 weechat-2.6

On recommendation of Sébastien Helleu a.k.a. FlashCode on IRC Freenode #weechat we should backport recent CVEs for 20.04 LTS:

$ gitlog v2.7..v2.7.1
5c0aa1aae 2020-02-20 20:45:08 +0100 N Sébastien Helleu Version 2.7.1
c827d6fa8 2020-02-14 08:14:31 +0100 N Sébastien Helleu irc: fix crash when receiving a malformed message 352 (who)
694b5c9f8 2020-02-14 08:11:02 +0100 N Sébastien Helleu irc: fix crash when a new message 005 is received with longer nick prefixes
51a739df6 2020-02-14 08:08:23 +0100 N Sébastien Helleu irc: fix crash when receiving a malformed message 324 (channel mode) (CVE-2020-8955)
410a12b2a 2020-02-14 08:05:19 +0100 N Sébastien Helleu Version 2.7.1-dev

I've added them on top of my earlier patch for LP #1866065 ("weechat python.so not linked against libpython3").

The attachment "python3: correctly find and link against libpython3.8, CVE-2020-8955" seems to be a debdiff. The ubuntu-sponsors team has been subscribed to the bug report so that they can review and hopefully sponsor the debdiff. If the attachment isn't a patch, please remove the "patch" flag from the attachment, remove the "patch" tag, and if you are member of the ~ubuntu-sponsors, unsubscribe the team.

[This is an automated message performed by a Launchpad user owned by ~brian-murray, for any issue please contact him.]

This bug was fixed in the package weechat - 2.6-2ubuntu2

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weechat (2.6-2ubuntu2) focal; urgency=medium

  * Correctly find and link against libpython3.8 (LP: #1866065)
  * CVE-2020-8955 fix crashes when receiving malformed messages
    (LP: #1872425)

 -- Tj <email address hidden> Mon, 13 Apr 2020 10:21:33 +0100