The CalDAV feature in httpd in Cyrus IMAP 2.5.x through 2.5.12 and 3.0.x through 3.0.9 allows remote attackers to execute arbitrary code via a crafted HTTP PUT operation for an event with a long iCalendar property name.
Created cyrus-imapd tracking bugs for this issue:
Affects: fedora-all [bug 1717829]
Exploitation of this flaw would need a calendar with a specially crafted property name longer than 256 characters. A HTTP PUT operation for a event on such a calendar would cause a stack-based buffer overflow of the propname stack variable. Successful exploitation would actually need some sort of shell code to be included in the calendar property name, which seems too far fetched, therefore successful remote code execution is difficult to achieve in this case.
Fixed upstream in 2.5.13 and 3.0.10:
This issue has been addressed in the following products:
Red Hat Enterprise Linux 8
Via RHSA-2019:1771 https://access.redhat.com/errata/RHSA-2019:1771
This bug is now closed. Further updates for individual products will be reflected on the CVE page(s):