Mahara 17.04 before 17.04.8 and 17.10 before 17.10.5 and 18.04 before 18.04.1 are vulnerable to mentioning the usernames that are already taken by people registered in the system rather than masking that information.
Severity
CVSS 3.0
5.3 medium
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
EPSS
0.9% chance of exploitation in the next 30 days; higher than 59% of CVEs (scores of 2026-10-31)