Open-Xchange: A specifically designed sieve script can cause a DoS in lib-sieve during sieve script compilation via NULL pointer dereference

Reproduction realcrash.sieve is the attached script 1. Build dovecot and pigeonhole 2. Run sievec realcrash.sieve Requirements include and variables extensions should be required. One of the global commands global/export/import without any arguments should be followed by the same command with val...