Univention Corporate Server 4.2 erratum 548 (extended maintenance)

This update addresses the following issues:
* Anonymity feature bypass via crafted web site (CVE-2017-16541)
* Memory safety bugs fixed in Firefox 62 and Firefox ESR 60.2
  (CVE-2018-12376)
* Use-after-free in driver timers (CVE-2018-12377)
* Use-after-free in IndexedDB (CVE-2018-12378)
* Out-of-bounds write with malicious MAR file (CVE-2018-12379)
* Setting a master password post-Firefox 58 does not delete unencrypted
  previously stored passwords (CVE-2018-12383)
* Crash in TransportSecurityInfo due to cached data (CVE-2018-12385)
* Type confusion in JavaScript (CVE-2018-12386)
* stack out-of-bounds read in Array.prototype.push (CVE-2018-12387)
* Memory safety bugs fixed in Firefox ESR 60.3 (CVE-2018-12389)
* Memory safety bugs fixed in Firefox 63 and Firefox ESR 60.3
  (CVE-2018-12390)
* Crash with nested event loops (CVE-2018-12392)
* Integer overflow during Unicode conversion while loading JavaScript
  (CVE-2018-12393)
* WebExtension bypass of domain restrictions through header rewriting
  (CVE-2018-12395)
* WebExtension content scripts can execute in disallowed contexts
  (CVE-2018-12396)
* WebExtension local file permission check bypass (CVE-2018-12397)