Moodle through 2.1.10, 2.2.x before 2.2.10, 2.3.x before 2.3.7, and 2.4.x before 2.4.4 does not consider "don't send" attributes during hub registration, which allows remote hubs to obtain sensitive site information by reading form data.
https://github.com/advisories/GHSA-x3x8-fjw6-hccx
https://moodle.org/mod/forum/discuss.php?d=228933
https://euvd.enisa.europa.eu/vulnerability/EUVD-2022-5705
http://openwall.com/lists/oss-security/2013/05/21/1
http://lists.fedoraproject.org/pipermail/package-announce/2013-May/107026.html
http://lists.fedoraproject.org/pipermail/package-announce/2013-May/106988.html
http://lists.fedoraproject.org/pipermail/package-announce/2013-May/106965.html
http://git.moodle.org/gw?p=moodle.git&a=search&h=HEAD&st=commit&s=MDL-37822