Recently, The open source version of Zimbra became unavailable on the official site and it seems that the main developers behind Zimbra are no longer actively developing Zimbra.
Before the open source version of Zimbra was taken offline I managed to save a few copies of it and the following are the versions that I have.
Please find below:-
zcs-7.2.5_GA_2906.RHEL6_64.20130911101145.tgz
zcs-7.2.6_GA_2926.RHEL6_64.20131203115858.tgz
zcs-8.0.5_GA_5839.RHEL6_64.20130910123908.tgz
zcs-8.0.8_GA_6184.RHEL6_64.20140925175705.tgz
zcs-8.0.8_GA_6184.RHEL7_64.20140925165850.tgz
zcs-8.6.0_GA_1153.RHEL6_64.20141215151155.tgz
zcs-8.8.15_GA_3869.RHEL6_64.20190918004220.tgz
