calendar/externallib.php in Moodle through 2.5.9, 2.6.x before 2.6.7, 2.7.x before 2.7.4, and 2.8.x before 2.8.2 allows remote authenticated users to obtain sensitive calendar-event information via a web-services request.
git.moodle.org/gw?p=moodle.git&a=search&h=HEAD&st=commit&s=MDL-48017
openwall.com/lists/oss-security/2015/01/19/1
github.com/moodle/moodle
github.com/moodle/moodle/commit/5770e5147838aa06a3ecdff6fc3aebbbd17fff90
github.com/moodle/moodle/commit/76aea854f6877cc5accb288bc6ac60bc55d30788
github.com/moodle/moodle/commit/c4250ef4f23776ff4862d2860b6be2cf7b2d85f6
github.com/moodle/moodle/commit/e83c756f84e16ab70e160e08deb84e9bc4bfbfea
moodle.org/mod/forum/discuss.php?d=278615
nvd.nist.gov/vuln/detail/CVE-2015-0215