All, probably not that important, because it only happened once in several months. Nevertheless for the sake of completeness:
same issue here, no wsgi, but PHP 7: ii apache2 2.4.25-3+deb9u4 ii apache2-data 2.4.25-3+deb9u4 ii apache2-utils 2.4.25-3+deb9u4 ii libapache2-mod-php7.0 7.0.27-0+deb9u1 ii apache2-bin 2.4.25-3+deb9u4 ii libapr1:amd64 1.5.2-5 ii libaprutil1:amd64 1.5.4-3 ii libaprutil1-dbd-sqlite3:amd64 1.5.4-3 ii libaprutil1-ldap:amd64 1.5.4-3 Apr 30 23:30:01 ftp17 kernel: [2384942.687542] apache2[6291]: segfault at 7f06f4973950 ip 00007f06f4973950 sp 00007ffec9db35c8 error 14 in libexpat.so.1.6.2[7f06f6bdc000+27000] [Mon Apr 30 23:30:01.204749 2018] [mpm_prefork:notice] [pid 6291] AH00169: caught SIGTERM, shutting down Last updates seem not to be related: Start-Date: 2018-04-04 07:47:47 Commandline: apt-get upgrade Upgrade: apache2-data:amd64 (2.4.25-3+deb9u3, 2.4.25-3+deb9u4), apache2-bin:amd64 (2.4.25-3+deb9u3, 2.4.25-3+deb9u4), apache2:amd64 (2.4.25-3+deb9u3, 2.4.25-3+deb9u4), apache2-utils:amd64 (2.4.25-3+deb9u3, 2.4.25-3+deb9u4) End-Date: 2018-04-04 07:47:51 Start-Date: 2018-04-26 11:14:04 Commandline: apt-get upgrade Upgrade: perl-base:amd64 (5.24.1-3+deb9u2, 5.24.1-3+deb9u3), perl-modules-5.24:amd64 (5.24.1-3+deb9u2, 5.24.1-3+deb9u3), libperl5.24:amd64 (5.24.1-3+deb9u2, 5.24.1-3+deb9u3), perl:amd64 (5.24.1-3+deb9u2, 5.24.1-3+deb9u3) End-Date: 2018-04-26 11:14:07 Issue occured only once, although apache is restarted every night since Dezember 2017!! I guess it's cosmic radiation, instable power supplies, cooling problems, broken hardware, running systems out of specification, or bad luck. - Chris -- Papst Franziskus ruft zum Kampf gegen Fake News auf. Wir finden, der Mann, der sich als Stellvertreter Christi ausgibt, von dem er behauptet, dessen Mutter sei zeitlebens Jungfrau gewesen, er hätte über Wasser gehen und selbiges in Wein verwandeln können, hat vollkommen recht.